Do you believe that humans caused global warming?? I think that humans may have done a little, but most of it is because things like this happen over time. I think that there really isn’t anything we can do to stop it if its actually happening, but if you want to act like your doing your part to save the planet then go right on ahead. How do you feel about it and why?? lol Eldude that could be true… you bastards jp ☻ Tweet This Post 30 Responses to “Do you believe that humans caused global warming??” Eldude: August 7, 2010 at 6:14 pm Farting vegetarians are the cause of global warming. matsystud: August 7, 2010 at 6:14 pm yes joe b: August 7, 2010 at 6:14 pm no i believe thats the way god wanted it… he wnated us all to die by our own destruction… thats why he didn’t stop it a_bush_family_member: August 7, 2010 at 6:14 pm No. The sun is causing the changes in the temperature. All of the planets have global warming, including pluto which is no longer called a planet. About Global Warming, What’s The Fastest Way To Let People Know That CO2 Is Not Causing Global Warming? http://answers.yahoo.com/question/index;_ylt=ApKTh4FA7ePHq_.saPvBy_Lty6IX? qid=20070523190743AAVacnI Also : 1) In several decades in the last century, temperatures fell when CO2 levels were increasing. 2) The earth was very hot 6,000 years ago (Holocene Thermal Maximum) and there were no SUVs back then.
Transcript
Do you believe that humans caused global warming??I think that humans may have done a little, but most of it is because things like this happen over time. I think that there really isn’t anything we can do to stop it if its actually happening, but if you want to act like your doing your part to save the planet then go right on ahead.
How do you feel about it and why??lol Eldude that could be true… you bastards ☻ jp
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30 Responses to “Do you believe that humans caused global warming??”
Eldude:August 7, 2010 at 6:14 pm
Farting vegetarians are the cause of global warming.
matsystud:August 7, 2010 at 6:14 pm
yes
joe b:August 7, 2010 at 6:14 pm
no i believe thats the way god wanted it… he wnated us all to die by our own destruction… thats why he didn’t stop it
a_bush_family_member:August 7, 2010 at 6:14 pm
No. The sun is causing the changes in the temperature. All of the planets have global warming, including pluto which is no longer called a planet.
About Global Warming, What’s The Fastest Way To Let People Know That CO2 Is Not Causing Global Warming?http://answers.yahoo.com/question/index;_ylt=ApKTh4FA7ePHq_.saPvBy_Lty6IX?qid=20070523190743AAVacnI
Also :1) In several decades in the last century, temperatures fell when CO2 levels were increasing.
2) The earth was very hot 6,000 years ago (Holocene Thermal Maximum) and there were no SUVs back then.
3) Ice core data (NASA) has shown there were faster increases in temperature thousands of years ago. In fact, the earth left the ice age in less than 20 years. Relative to the age of the earth, 20 years is equivalent to a second.
4) There were high CO2 levels thousands of years ago and there were no SUV’s back then. High temperatures quickly cause the release of CO2. Elevated temperatures cause CO2 to be released by the ocean, by melting ice, by melting permafrost, etc.. Also, it has never been proven that CO2 drives the temperature of the planet. Ancient ice cores samples have proven CO2 never drove temperature changes in the past. Why would CO2 drive temperatures now?
Is The CO2 Global Warming Theory Now A Religion?http://answers.yahoo.com/question/index;_ylt=AnAePgO6iZY9Mn1jMxauqOLty6IX?qid=20070605152527AA3NdyX
Another poster mentioned the dust storms of China are caused by global warming or Genghis Khan. He is wrong. China has has dust storms for centuries. Dust flys off of the Gobi Desert. There is no way Genghis Khan could make a 500,000 square mile desert that is 3,000 feet high. http://veimages.gsfc.nasa.gov/2681/Gobi.A2002074.0335.250m.jpg
Mar’s global warming is exactly as the Earth’s and it is caused by the sun."These parallel global warmings — observed simultaneously on Mars and on Earth — can only be a straightline consequence of the effect of the one same factor: a long-time change in solar irradiance.""The sun’s increased irradiance over the last century, not C02 emissions, is responsible for the global warming we’re seeing, says the celebrated scientist, and this solar irradiance also explains the great volume of C02 emissions."http://www.canada.com/nationalpost/story.html?id=edae9952-3c3e-47ba-913f-7359a5c7f723&k=0
LuLu:August 7, 2010 at 6:14 pm
Yes defintitely
Mad:August 7, 2010 at 6:14 pm
NO NO NO NO NO we do not cause global warming and it has been proven the sea emits more co2 than we do its all aload of balls
look for a documentry called global warming swindle chanel 4
ronedon:August 7, 2010 at 6:14 pm
Solar cycles play the biggest part.
Brian:August 7, 2010 at 6:14 pm
The sun caused glabal warming! I feel it happen each morning- it gets warmer as the day goes on.
special-chemical-x:August 7, 2010 at 6:14 pm
The next time you go our to your car on a hot day and open the door and the amzingly hot inside air of the car comes out, I want you to think about whether or not humans can trap the energy of the sun on this earth by their creations.
Some of these creations are clothing. Black colored clothing is hotter in the sun while white colored clothing is cooler because it reflects the sun ray energy back up into space.
Another creation of humans are various gases we pollute the atmosphere with. Though invisible to OUR eyes, they act just like clothing.
WWe_Fan:August 7, 2010 at 6:14 pm
SKIN IS OVERRATED!!!tumors are betterthere more special
But its O.K because green monkeys ATE MY skin. LOL
of corse humans CONTRIBUTE to global warming but there was a volcanoe that erupted in Fiji lately that gave out as much carbon emmisions as 2.5 million cars all running for 24 hours.
MAL:August 7, 2010 at 6:14 pm
I disagree with joe b because God doesn’t control our descisions. He gave us free will and if we choose to destroy the earth that he gave us then i guess we can do it.. it states two times in the bible to not destroy the earth. i believe its a wonderful blessing. i know this science part is kinda long so sorry –
There is one factor telling us global warming is not true. That is that they earth goes through temp. cycles. I don’t see why global warming can’t happen ontop of that. there are so many ways to prove it. can you deny the fact that we emit tons and tons of CO2 just from our fridges each year? that is a greenhouse gas, and it is a proven fact that nobody can even try to deny, that it traps heat in our atmosphere. We are at a critical point in time these days because until now, the oceans and other large bodies of water have absorbed CO2 like a sponge. Now, imagine a leaking sponge, completely full. Well are oceans are completely saturated, meaning all the CO2 that can possible dissolve in it already has. Now where does the CO2 go? i could go onnn and on about the science to back it up but i would literally be here until 9:30 and still not even tell the half of it
Wayne ahrRg:August 7, 2010 at 6:14 pm
What happens over time is mostly equilibrium and / or negative feedback- otherwise things start to go off in one direction.
E.g. no animals – just plants and you get over oxygenation – as happened in the carboniferous age – big trees – not many animals – Giant insects etc.
nature settled down over a few epochs to where we are now – and then Bam -world population goes from millions to 100s billions in just two hundred years – and release all those millions of years of stored up solid Carbon as CO2 in less time it takes a snow flake to get down the bottom of glacier – and chuck in a wealth of methane (worse than CO2) and yeah – who else you gonna finger for it – the pigeons for cooing too much?
So the equilibrium is out of whack – there is no negatve feedback (when foxes overbreed – the rabbit population falls away and lo less foxes next year – less foxes = more rabits ad infinitum) – and nature’s got habit of pulling real nasty snap-backs. Mankind says – oooh this coal and oil stuff is running out – let’s burn it faster!
juicyah:August 7, 2010 at 6:14 pm
trees attract rain ,no trees no rain,no rain temperature increases, which is global warming,a disaster awaiting planet earth
awesomemanforthelord:August 7, 2010 at 6:14 pm
What’s global warming? Just kidding. yes but i dont think were the problem.
bfwh218:August 7, 2010 at 6:14 pm
Is this a trick question? Or are you really that stupid? Thanks for your permission so that I can ‘do my part’; I feel so much better now….
byderule:August 7, 2010 at 6:14 pm
Go to the jungles of Oaxaca,the ex forrests of Africa ,see the desertification in Mexico,the dust storms in northern China .
compare todays situation with what the place used to look like .And understand how People have totaly changed their Environment and subsequently their climate.Add all of this together,from all over the globe, and calculate the results .
MAN MADE CLIMATIC CHANGES
We cannot save the world from global warming ,but we still need our Environment to survive whilst we are still here .
Everybody is so desperate to absolve humanity from blame ,and this is not possible
Global warming is one thing ,and for many people it seems to be the knight on a white horse that saysdont worry it is not your fault you can do nothing about it ,keep on trucking ,poluting, deforesting, desertifying,keep killing the animals ,keep burning the woods
Man is responsible for much climate change it cannot be whitewashed by Global warming
If Global warming now also want to change the climate it has to stand in linebecause it is not the only one
ONCE UPON A TIMEI went to the jungles of Oaxaca and discussed with the Natives the mountain before us ,Mostly deforrested ,scarred by landslides and dotted with madly steep corn patches (which only produced for 3 years ),and devoid of clouds.
They all agreed that the days were hotter ,there was less rain ,And the river was dry part of the year.
When they were boys ,the river was bigger and ran all year around,the mountain was always covered in clouds with daily rains .And the days were more bearable .
Their actions in the desperate plight to feed their enormous families of avarage 12 kids per family ,often much more ,had destroyed their home ground with indisputable climate changes.They had changed their climate.This happens all over Mexico
In Africa I have seen lush wooded lands change into dessert within a few years by large invading comunities ,who devoured the trees for building and firewood ending up in a dessert with out waterand with a hot sun under which no new plantation was possible.The people had changed their climate,this happens all over Africa.
In Northern china two mayor dessert are merging and 900 vilages are buried under the dust ,thousands of refugee farmers who had changed their climate ,by intensive agressive agriculture are fleeing for their lives,
This happens all over the world .it happened in the 20ties in the USA has everybody forgotton that ,was this not a climate change ?
Granted the climatic changes are local ,but effects neighboring areas ,there is less rainfall, rivers dry up ,
Collectively because there is so much of it all over the world ,the global precipitation is affected and so is the climate .
And who did it ???
the people are changing the climate
Like Ghengas Kahn changed the climate when he burned all the forests and filled the wells with sand ,Like the Phoenicians changed the climate of lebanon to build the trading fleet .Like the Spanish climate was changed by using their forest to build the Armada ,
So are we today changing the climate by massive deforestation,agressive corporate farming (using chemicals),overgrazing ,overpumping deep subteranean waters ,ignorence and impartiality
Global warming.carbon emisions ,polution ,sunspots ,solar flares,hairsprays , Al Gore, and skeptics are the rasberries on top
and read up what America is planning with the insane master plan for Ethanol production.http://answers.yahoo.com/question/index;_ylt=AjHWwGGffFFtirnd17BsN.nty6IX?qid=20070530195737AACbd5b&show=7#profile-info-fHbzOdoIaaSeems as if America is trying to compete with Global warming
I wonder who will win.?but who ever it is ,the rest of the world looses.
we are in trouble,and if we can do something that will make it less ,we should try to do it .
And there are many things that we can improve onso that ,we can at least last as long as posible .
Anders:August 7, 2010 at 6:14 pm
Historically CO2 has lagged 200 – 1000 years behind the rise in temperature. It has, in the past, acted as a very strong amplifying effect to global warming. The initial cause has been various natural cycles. Now we see a direct correlation between the rise in CO2 and in temperature. As humans release CO2 in to the atmosphere it traps more heat on Earth. This leads to more CO2 being released (as in the past), thus CO2 is presently BOTH a cause and a strong amplifier. This is not the natural order but man made. Appropriate name btw.
a_bush_family_member, there are 173 planets/satellites and only 6 have of them have been said to be warming. Mars, for instance does not experience global warming. One of it’s polar ice caps is melting which is a regional phenomena and is explained by the dust storm that is raging there. Now if it was the Sun then every body in the solar system would be heating, which they are not.Regarding solar output. This is very precisely measured and the energy increase is not enough to achieve this effect. It is estimated that the Sun stands for 10% of the temperature increase.
puggirl93:August 7, 2010 at 6:14 pm
i pensonally believe that all global warming is garbage, there are lots of science to prove my point! there is no science to prove global warming
dana1981:August 7, 2010 at 6:14 pm
Yes, humans are the primary cause of global warming. Every single person here who said we aren’t explained why not with misinformation.
I’m not going to explain all the evidence that humans are the primary cause of global warming. That’s been discussed here hundreds of times. For starters, climatologists are convinced that humans are the main cause of the recent global warming, and if you think you know better than them, you need a serious ego check. Secondly, just look at this plot of global temperature over the past century and a global climate model to see what the primary cause of the warming is.
Heck No! And Al Gore is a hypocrite to tell everyone that humans cause global warming.After all, he is the one flying aroung the globe in earth-polluting-jets complaing that WE are destroying the planet…
brtbbsngnt:August 7, 2010 at 6:14 pm
Yes why would New Jersey,Pennsylvania,NYC,NY State.Keep building more highways.For more cars.
Earnest T Bass:August 7, 2010 at 6:14 pm
they helped
Dai D:August 7, 2010 at 6:14 pm
It WAS humans. We set up these smoke factories, we drive cars, we pollute lakes and rivers. Its all our fault.
Julian D:August 7, 2010 at 6:14 pm
No. And I’m not a Bush supporter either. Global warming is caused by the same cycle that causes the ice ages. We’re still coming out of the last one so, naturally, it’s getting warmer. Contrary to all the hype, the warming is what is causing the increase levels of CO2, not the other way around. CO2 is actually a pretty good thing. Plants need CO2, and the more CO2 there is, the faster and healthier plant life grows, the more Oxygen they produce (hey, we like Oxygen), which in turn helps life flourish all the way up. Ironically, increased levels of CO2 help combat other problems environmentalists go on about: deforestation and extinction.
There is no way we can stop global warming. Just as soon try to stop the sun from fusing. But it has been much hotter in the Earth’s history. Coral has lived through it all so I’m sure we can too. And notions that there are going to be sudden, disasterous changes (like rising sea levels) are ridiculous. These things might take even 1,000 years, so we’d hardly notice in the short-run.
That’s not to say we can’t support things that reduce human impact/pollution on the environment. We should do that, because we do have an impact. Supporting anything that increases efficiency, decreases waste, and saves money is a great thing.
labohemianartist:August 7, 2010 at 6:14 pm
it doesn’t matter if it is our fault or not. we still should CHERISH this world. for tis is all we’ve got and we may as well try to take care of it as much as possible.
kat s:August 7, 2010 at 6:14 pm
Yes and NO!!We are just now realizing how our selfish bad choices are affecting the earth. But it is almost impossible to not contribute in some way on a daily basis.However the earth is smart and she has a way of healing herself. Maybe this is part of the process.
Keith J:August 7, 2010 at 6:14 pm
Yes I do because by using cars and trucks it puts carbon dioxide in the air and that goes to our atmosphere causing more heat to go through our atmosphere than out which make our climate hoter than it should be. Thats why the north and south poles ice, is breaking away. What we need to do is stop making cars that run on gasoline and start making them run on solar energy so we wont have to use propane which makes these fuels for cars, trucks, planes, and jets. I learned this all for science class.
DaDa:August 7, 2010 at 6:14 pm
I don’t believe that we humans "caused" global warming. It is a natural process. The earth and the sun are aging. I do believe, that we humans are speeding up the process of global warming.
Memphis Chrissy:August 7, 2010 at 6:14 pm
Its mostly our fault cause people drive hummers and suvs and throw trash out on the highway and cut down trees and have nuclear power plants and dont think and supprt bush and stick up for paris hilton and ACT LIKE RETARDS!!!
David M:August 7, 2010 at 6:14 pm
When I was doing research on global warming, I came upon an article that began with a brilliantly insightful quote by 19th century German philosopher Arthur Schopenhauer. He said that “There is no opinion, however absurd, which men will not readily embrace as soon as they can be brought to the conviction that it is generally accepted.” I want you to keep this quote in mind as you read my post, and think about whether it applies to you.
When people ask me whether global warming is fact or fiction global warming is actually both fact and fiction. The average temperature of the earth has risen by about 1°F in the last century, and we can expect significantly greater temperature increases in the next hundred years. Those are facts. But the concept of man-made global warming and the idea that climate change is going to bring about some sort of catastrophic end of the world, those are completely fictitious.
I’m going to start with fiction number one, which says that the main cause of global warming is greenhouse gases released by human activity. This is simply untrue. The earth’s temperatures have always fluctuated between hot and cold and that is a scientifically proven fact. Indeed, after studying of the growth rings of ancient trees, scientist Keith Briffa of the University of East Anglia has concluded that the earth’s climate has, in the past, shifted from hot to cold in as little as 30 years. Our current climate is not changing nearly that quickly, and there is every reason to believe that the change is being caused by natural factors outside of our control, such as the magnetic field of the sun, which has more than doubled in strength in the 20th century. This increased magnetic field has been trapping more and more cosmic rays, and therefore fewer of these rays have been reaching the earth’s atmosphere. This is important because experiments performed by Danish scientist Henrik Svensmark have conclusively proven that these cosmic rays are one of the main ingredients necessary for low-altitude clouds to form. Since fewer cosmic rays have been reaching the earth, there have been fewer clouds to reflect sunlight, and so more and more of the sunlight has remained in the atmosphere, heating the planet and causing our current global warming trend.
It should be noted that the greenhouse effect is a very real force, and it is responsible for much of the warmth in our atmosphere. However, it should also be noted that while carbon dioxide, the gas that alarmists blame for global warming, is indeed a greenhouse gas, it is not the most important greenhouse gas. All scientists will agree that water vapor is responsible for at least two thirds of the greenhouse effect, and many scientists believe that water vapor is responsible for 95% of the greenhouse effect. Scientists also agree that human activity has had no affect whatsoever on the concentration of water vapor in the atmosphere. Humans have undoubtedly raised carbon dioxide concentration to an unprecedented level, but since carbon dioxide is only responsible for a small percentage of the greenhouse effect and human activity is only responsible for a small percentage of atmospheric carbon dioxide, this change has probably not had a significant effect on the earth’s climate.
Yet despite this evidence, most people still readily embrace the myth of man-made global warming. After all, the recently released fourth IPCC Assessment Report claims to represent an unequivocal scientific
consensus on the matter. Yet when one looks at the facts, one sees that the Intergovernmental Panel on Climate Change is a political group with a political agenda, and their results arise from a shocking mix of bad science and flagrant dishonesty.
The IPCC says it bases much of its research on statistical techniques, yet does not employ any credible statisticians. When a pro-bono committee of statisticians, led by Dr. Edward Wegman, was asked to review the IPCC’s third assessment report, they found numerous statistical errors that drastically altered the results. When these errors were corrected, all evidence indicating that this is the hottest century in the last thousand years, ceased to exist. The IPCC’s only response to these findings was to assert that although their methods may have been flawed, their results were still correct. But, ladies and gentlemen, facts based on fictions are not facts at all.
Furthermore, the IPCC is so determined to lay blame on the United States and others that they are actually willing to mislead to the public about their findings. Dr. Chris Landsea, one of the world’s preeminent experts on hurricanes, resigned from the IPCC because it would not stop making press releases completely contrary to his findings. Landsea had found no conclusive links between hurricanes and global warming and yet the IPCC refused to stop announcing that global warming caused hurricanes. Dr. Landsea wrote an open letter stating that “I personally cannot in good faith continue to contribute to a process that I view as both being motivated by pre-conceived agendas and being scientifically unsound.”
The only reason that you have not heard more criticisms directed towards the IPCC is that those who do speak out are shunned and silenced. They are equated to fiction fanatics, UFO buffs, and holocaust deniers, when in fact they are some of the most brilliant and accomplished scientists in the world. But they are afraid to voice their concerns, and very reasonably so. When Henk Tennekes, one of the pioneers of meteorology, began calling the IPCC’s mathematical models unreliable, he was quickly ousted from the Royal Netherlands Meteorological Institute. Since then, most dissenting scientists have chosen to keep their heads down and their mouths closed where global warming is concerned.
Now let’s talk about another school of fiction spun regarding the consequences of global warming. I’m sure you’ve been alarmed by the various Chicken Little scientists and politicians who scurry around screaming “the sky is falling, the sky is falling.” Or rather “the ice is melting, the ice is melting.” People like Al Gore, whose documentary, An Inconvenient Truth, demonstrates very little besides a passion for theatrics and a complete ignorance of basic chemistry. Al Gore promotes the inconvenient fiction that since increased carbon dioxide levels have historically accompanied increased temperatures, the carbon dioxide must be causing the increased heat. In fact, it is the other way around, because a great deal of the earth’s carbon dioxide and other greenhouse gases are stored in the oceans. When temperatures increase, more carbon dioxide is released from the sea into the atmosphere, because warmer water cannot hold as much gas. So increased greenhouse gas levels have historically been a result of global warming, not a cause. And for Al Gore, this is a very inconvenient truth indeed.
And while we’re on the subject of fiction-spreading alarmists, we should talk about Dr. Stephen H. Schneider, Professor of Environmental Biology and Global Change at Stanford University, and one of the leading proponents of the “The Sky is Falling” theory. Dr. Schneider jumped on the global warming bandwagon in the 1980s, and has since then demonstrated his impartiality and sound scientific method by actually admitting, and I quote," I don’t set very much store by looking at the direct evidence." He then all but admitted his role in fabricating fiction when he said that "[We] have to offer up scary scenarios, make simplified dramatic statements and make little mention of any doubts we may have. Each of us has to decide what the right balance is between being effective and being honest."
It’s scary to think that kids are being “educated” with the fictions of people like Dr. Stephen Schneider, including the numerous tales of the so-called catastrophic effects of global warming. But let’s forget those myths for a moment and talk fact. If the earth’s average temperature rises 4 or 5 degrees Fahrenheit in the next century, as is currently projected, we can expect a return to a climate similar to that of the Medieval Warm Period of 800-1300A.D., when it was so warm that the Norse were able to pasture animals and grow hay in Greenland. During the Medieval Warm Period, which is also known as the LITTLE CLIMATE OPTIMUM, crops (and plants in general) grew far better and people around the world were much better fed than in the cooler centuries afterwards.
Now that it’s been established that plants would continue to thrive in warmer environments, you might be wondering about animals. Well, most animals on this planet evolved thousands of years ago, and those unable to adapt to slightly warmer climates died out during the Medieval Warm Period or during previous natural periods of warming, so the animals of earth, including us, would really have nothing to worry about.
The final fiction I want to address is the much loved fable that the polar ice caps will melt, the oceans will rise, and coastal cities will be drowned. None of those things happened during the Medieval Warm Period, so there is no reason to expect them now. We especially don’t have to worry about the South Pole, since parts of Antarctica have actually cooled by over 1˚F in the last decade or so. As for the Arctic, Dr. Vera Alexander has stated that while some parts might indeed melt in future summers, the vast majority of the ice would refreeze in the winter. In addition, any melting ice will probably be replaced by the increased snow fall caused by warmer climates. Also, Dwight Billings and Kim Moreau Peterson predict that such a
warming would have no major species impact in the arctic. Remember, all of the arctic species have survived warm periods before. There is no reason to readily embrace the fiction that this time will be any different.
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Sunday, 26 September, 2010
Does breathing contribute to CO2 buildup in the atmosphere?Guest post by Kate from ClimateSight
The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact.
More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below, glucose) in the oxygen that we breathe in to yield carbon dioxide and water, which we exhale as waste products, as well as energy, which is required to maintain our bodily processes and keep us alive.
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy
carbohydrates + oxygen → carbon dixoide + water + energy
It should come as no surprise that, when confronted with the challenge of reducing our carbon emissions from the burning of fossil fuels, some people angrily proclaim, "Why should we bother? Even breathing out creates carbon emissions!"
This statement fails to take into account the other half of the carbon cycle. As you also learned in grade school, plants are the opposite to animals in this respect: Through photosynthesis, they take in carbon dioxide and release oxygen, in a chemical equation opposite to the one above. (They also perform some respiration, because they need to eat as well, but it is outweighed by the photosynthesis.) The carbon they collect from the CO2in the air forms their tissues - roots, stems, leaves, and fruit.
These tissues form the base of the food chain, as they are eaten by animals, which are eaten by other animals, and so on. As humans, we are part of this food chain. All the carbon in our body comes either directly or indirectly from plants, which took it out of the air only recently.
Therefore, when we breathe out, all the carbon dioxide we exhale has already been accounted for. By performing cellular respiration, we are simply returning to the air the same carbon that was there to begin with. Remember, it's a carbon cycle, not a straight line - and a good thing, too!
This post is a new rebuttal to the skeptic argument 'Breathing contributes to CO2 buildup' (written by Kate from ClimateSight). This blog post is the Intermediate version- she's also written a Basic Version that features a simple graphic explaining the carbon cycle from a respiration point of view.
1. Doug Mackie at 14:50 PM on 26 September, 2010I published this in Eos, the newspaper of the American Geophysical Union, in 2006.
I was searching for a way to tell merkins that they emit too much. The article is severely constrained by space but the really essential point is that there are many nations that ‘emit’ more CO2 from their population breathing than they do from burning fossil fuels.
The rationale for the article was a ‘helpful’ suggestion of a method for the US to further destabilise Kyoto (this was in 2006) by insisting that human respiration be included on the flimsy pretext that enteric methane is included. The idea (from the US pov) would be that China especially would have to pay a greater proportion of its GDP to buy credits than the US.
Please, note the ‘department’ of Eos that this was published in before telling me that breathing does not release fossil CO2.
2. Doug Mackie at 14:52 PM on 26 September, 2010hey that didn't work.Here is the link:http://www.agu.org/pubs/crossref/2006/2006EO340007.shtml
3. RSVP at 17:36 PM on 26 September, 2010"By performing cellular respiration, we are simply returning to the air the same carbon that was there to begin with. "
If plants cant distinguish fossil CO2 from any other CO2, and the concentration of CO2 in the atmosphere has nearly doubled, it is likely that a good part of what we eat has its origin in petroleum.
4. Renegadeguy at 18:14 PM on 26 September, 2010This article doesn't really answer the question of whether a massive increase in the human population over the last couple of centuries has had an overall effect on CO2 emissions from breathing. And how humans reducing other species on the planet has made any difference.
5. RSVP at 18:31 PM on 26 September, 2010Renegadeguy #4"And how humans reducing other species on the planet has made any difference."
You could have less diversity in terms of species, but still
The Phony War: Lies, Damn Lies and the IPCCIt seems ironic that one key version of this argument – that the IPCC ‘misleads’ by misrepresenting the science of climate change and its potential consequences - is itself a gross misrepresentation of a statement made by Professor Mike Hulme, a climate change scientist who works at the University of East Anglia. He was also co-ordinating Lead Author for the chapter on ‘Climate scenario development’ for the IPCC’s AR3 report, as well as a contributing author for several other chapters. This is how Hulme dismissed the claim:
"I did not say the ‘IPCC misleads’ anyone – it is claims that are made by other commentators, such as the caricatured claim I offer in the paper, that have the potential to mislead."
The same argument also has a broader scope, demonstrated by the claim that within the IPCC, there is a politically motivated elite who filter and screen all science to ensure it is consistent with some hidden agenda. This position turns the structure of the IPCC into an argument, by claiming that the small number of lead reviewers dictate what goes into the IPCC reports.
Before considering this argument in full, it is prudent to observe that the IPCC does no science or research at all. Its job is purely to collate research findings from thousands of climate scientists (and others working in disciplines that bear on climate science indirectly, such as geology or chemistry). From this, the IPCC produces ‘synthesis reports’ – rather like an executive summary – in which they review and sum up all the available material. It is necessary therefore to have an organisational structure capable of dealing efficiently with so much information, and the hierarchical nature of the IPCC structure is a reflection of this requirement.
How does the process work? The IPCC primarily concerns itself with science that has been published in peer-reviewed journals, although, as it makes clear in the IPCC’s published operational appendices, it does also use so called ‘grey’ material where there is insufficient or non-existent peer-reviewed material available at the time the reports are prepared. See IPCC principles, Annex 2: Procedure for using non-published/non-peer-reviewed sources in IPCC reports. Many people are involved in this complex process:
“More than 450 Lead Authors and more than 800 Contributing Authors (CAs) have contributed to the Fourth Assessment Report (AR4)".
Source: The role of the IPCC and key elements of the IPCC assessment process, February 2010
To suggest the IPCC can misrepresent the science belies the fact that such misrepresentations would be fiercely criticised by those it misrepresented. Considering how many lead authors and
contributors are involved, any egregious misrepresentation would hardly remain unremarked for very long.
The Broader Consensus
As with all such disputes, it is helpful to consider if there is any evidence of credible independent support for the reports the IPCC has produced, and the conclusions those reports contain. If the accusations were true, such misrepresentation would also be problematic for official bodies, particularly national science academies and the like.
On that basis, it is reassuring to note that nearly every major national scientific body e.g. the Royal Society (UK) or the National Academy of Sciences (US), unreservedly supports the work and findings of the IPCC. An expanded list can be found here, including this statement:
“With the release of the revised statement by the American Association of Petroleum Geologists in 2007, no remaining scientific body of national or international standing is known to reject the basic findings of human influence on recent climate change”.
In 2010 an independent investigation of the IPCC was launched. Conducted by the InterAcademy Council, which represents the world’s scientific academies, the report highlighted a number of organisational and procedural areas that the council felt could be improved. However, the recommendations did not detract from the council’s appreciation of the IPCC’s work:
“The Committee found that the IPCC assessment process has been successful overall. However, the world has changed considerably since the creation of the IPCC, with major advances in climate science, heated controversy on some climate-related issues, and an increased focus of governments on the impacts and potential responses to changing climate”.
Source: IAC Report Executive Summary
Like all organisations, the IPCC can improve on its performance. Recent defensiveness regarding errors or ambiguities in the AR4 report may be mitigated in light of unpleasant attacks on the organisation and its director, but the criticisms are valid none the less.
However, claims that the IPCC does not accurately represent the views and findings of the scientists, on whose work the IPCC reports are based, are not supported by the facts.
This post is the Intermediate Version (written by Graham Wayne who rewrote my rather brief and rushed original version) of the skeptic argument "The IPCC consensus is phoney".
Posted by gpwayne at 11:11 AM
Printable Version | Link to this page
Comments
Comments 1 to 18:
1. miekol at 11:30 AM on 25 September, 2010" it is prudent to observe that the IPCC does no science or research at all"
Precisely, its a politcal committee, enough said.
Except it should be called the ICCC. They couldn't even present their name right.
2. archiesteel at 11:34 AM on 25 September, 2010@miekol: I don't get it. Aren't panel and committee synonyms?
3. kdkd at 11:37 AM on 25 September, 2010"it is prudent to observe that the IPCC does no science or research at all"
Nope this is incorrect. Collating the work of others, and subjecting it to analysis is an important part of the research process. Perhaps Graham means that "it is prudent to observe that the IPCC does no primary scientific research"?
4. Roger A. Wehage at 11:44 AM on 25 September, 2010You use IPCC without defining it. That is rude. It forces readers unfamiliar with the subject to go elsewhere for a definition.
Always define an acronym when first introduced.
5. gallopingcamel at 14:15 PM on 25 September, 2010John,
On a couple of occasions when the subject has been Tamino and his ilk you have deleted my use of the quote attributed by Mark Twain to Benjamin Disraeli:
"There are three kinds of lies: lies, damned lies and statistics."
Now you are paraphrasing the quote to head this post but I do not object. You hit the right target!
6. Daniel Bailey at 14:53 PM on 25 September, 2010Re: gallopingcamel (5)
"On a couple of occasions when the subject has been Tamino and his ilk you have deleted my use of the quote attributed by Mark Twain to Benjamin Disraeli:
"There are three kinds of lies: lies, damned lies and statistics." "
GC, your usage of "ilk" in conjunction with your quote should be in violation of the comment policy, as it is tantamount to an accusation of deception and/or dishonesty. The fact that you openly admit to doing this previously and having it deleted each time is troubling enough.
It is hard enough to maintain one's own decorum & be a positive factor on this blog without comments like yours inviting a likewise response.
I've already "really not helped" once tonight. And you're not helping me now.
The Yooper
7. kdkd at 14:54 PM on 25 September, 2010gallopingcamel #5
Presumably this is because that quote can be used in an ironic / self deprecating sense, or it can be used in an attempt to reject the entire field of statistics. This latter usage is destructive solipsistic nonsense.
As someone who is reasonably experienced at using statistics, I can assure you that used appropriately statistics can be highly informative. Understanding how to do so is a fairly arduous task, and I have particularly enjoyed teaching undergraduate science some of the core skills for the appropriate use of statistics.
8. RSVP at 15:04 PM on 25 September, 2010What I get out of this article. The IPCC is an impartial bureaucracy with a name that implies climate is changing.
9. Daniel Bailey at 15:09 PM on 25 September, 2010Re: RSVP (8)
Perhaps you should read more than just the title then.
Or if you'd like a different place to start to learn about our changing of our climate, ask.
"Fill your mind with the coppers of your pockets and your mind will fill your pockets with gold."
The Yooper
10. Phila at 16:17 PM on 25 September, 2010#8 RSVP
What I get out of this article. The IPCC is an impartial bureaucracy with a name that implies climate is changing.
Sounds like what you get out of it is what you bring to it.
11. Nichol at 19:42 PM on 25 September, 2010Would it be reasonable to compare the IPCC process with the way Wikipedia tries to collate knowledge in general, trying to have a neutral point of view, and not contributing original findings, but to refer to information published elsewhere.
Only the IPCC work is not done by random volunteers, but by actual experts in the field. And the requirements for the referenced literature are much more serious. And the editing process is more strictly defined and negotiated.
12. scaddenp at 19:47 PM on 25 September, 2010Meikol - to call it a "political" committee would require you produce some proof that it advocates some political perspective. Instead the panel seeks to inform the political process by reviewing the best opinion of science. Can you honestly say that you dont think WG1 represents the published science?
13. scaddenp at 19:50 PM on 25 September, 2010GC - do really believe that quote (which I think is accurate about misuse of statistics by politicians) applies to science? Science in all fields absolutely depends on statistics. How else to understand error? Your quote illuminates nothing in my opinion.
14. J Bowers at 20:07 PM on 25 September, 20101 miekol -- "Precisely, its a politcal committee, enough said."
No, it's an apolitical panel of scientific experts. The only way the panel and the experts are
political is in the way they are used as political footballs by politicians and economically vested organisations.
15. Alexandre at 21:39 PM on 25 September, 2010"Precisely, its a politcal committee, enough said."
I love this kind of approach. It's like reading a paper then finding a sentence like "the uncertainty range is..." and nailing it: "aha! they just don't know it!"
To be a denier, you must carefully keep distance from the big picture.
16. Phil at 23:05 PM on 25 September, 2010The actual acronym is IPoCC not - as miekol @1 implies - IPfCC. Roger @4 is right- it should have been defined. If it had been then RSVP @8 wouldn't have needed to do the research he clearly didn't do. So although the advice "The Yooper" @9 presents is good, actually simply reading the correct title (rather than miekol's misrepresentation) would have been sufficient.
The Intergovernmental Panel on Climate Change
17. beam me up scotty at 04:07 AM on 26 September, 2010The critique as spoken by the critic is very reasonable. http://www.pbs.org/wnet/need-to-know/the-climate-desk/audio-after-glaciergate-un-panel-on-climate-change-mulls-reforms/3673/
When the information gets into the hands of the deniers... different story.
I doubt there are many sincere skeptics anymore. There are of course many members of the denier cult. I don't think they can be reached.
18. ProfMandia at 04:50 AM on 26 September, 2010Despite strong political reasons for them not to endorse, the following countries endorsed the IPCC 2007 reports because the science was undeniable:
United States of America - Fossil fuel-based economy, strong lobby efforts opposed to regulating fossil fuel emissions
Saudi Arabia - World's largest producer/exporter of oil
China - Rapidly industrializing using coal-fired power plants
India - Rapidly industrializing using coal-fired power plants
The IPCC WGI Report (2007) concluded: “Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”
130 countries endorsed the reports, and since 2007, no scientific body of national or international standing has maintained a dissenting opinion.
The Big PictureOftentimes we get bogged down discussing one of the many pieces of evidence behind man-made global warming, and in the process we can't see the forest for the trees. It's important to every so often take a step back and see how all of those trees comprise the forest as a whole. Skeptical Science provides an invaluable resource for examining each individual piece of climate evidence, so let's make use of these individual pieces to see how they form the big picture.
The Earth is warming
We know the planet is warming from surface temperature stations and satellites measuring the temperature of the Earth's surface and lower atmosphere. We also have various tools which have measured the warming of the Earth's oceans. Satellites have measured anenergy imbalance at the top of the Earth's atmosphere. Glaciers, sea ice, and ice sheetsare all receding. Sea levels are rising. Spring is arriving sooner each year. There's simply no doubt - the planet is warming.
And yes, the warming is continuing. The 2000s were hotter than the 1990s, which were hotter than the 1980s, which were hotter than the 1970s. 2010 is on pace to be at least in the top 3 hottest calendar years on record. In fact, the 12-month running average global temperature broke the record 3 times in 2010, according to NASA GISS data. Sea levels are still rising, ice is still receding, spring is still coming earlier, there's still a planetary energy imbalance, etc. etc. Contrary to what some would like us to believe, the planet has not magically stopped warming.
Humans are causing this warming
There is overwhelming evidence that humans are the dominant cause of this warming, mainly due to our greenhouse gas emissions. Based on fundamental physics and math, we can quantify the amount of warming human activity is causing, and verify that we're responsible for essentially all of the global warming over the past 3 decades. In fact we expect human greenhouse gas emissions to cause more warming than we've thus far seen, due to the thermal inertia of the oceans (the time it takes to heat them). Human aerosol emissions are also offsetting a significant amount of the warming by causing global dimming.
There are numerous 'fingerprints' which we would expect to see from an increased greenhouse effect (i.e. more warming at night, at higher latitudes, upper atmosphere cooling) that we have indeed observed. Climate models have projected the ensuing global warming to a high level of accuracy, verifying that we have a good understanding of the fundamental physics behind climate change.
Sometimes people ask "what would it take to falsify the man-made global warming theory?". Well, basically it would require that our fundamental understanding of physics be wrong, because that's what the theory is based on. This fundamental physics has been scrutinized through scientific experiments for decades to centuries.
We also know that if we continue to emit large amounts of greenhouse gases, the planet will continue to warm. We know that the climate sensitivity to a doubling of atmospheric CO2 from the pre-industrial level of 280 parts per million by volume (ppmv) to 560 ppmv (we're currently at 390 ppmv) will cause 2–4.5°C of warming. And we're headed for 560 ppmv in the mid-to-late 21st century if we continue business-as-usual emissions.
The net result will be bad
There will be some positive results of this continued warming. For example, an open Northwest Passage, enhanced growth for some plants and improved agriculture at high latitudes (though this will require use of more fertilizers), etc. However, the negatives will almost certainly outweigh the positives, by a long shot. We're talking decreased biodiversity, water shortages, increasing heat waves (both in frequency and intensity), decreased crop yields due to these impacts, damage to infrastructure, displacement of millions of people, etc.
Arguments to the contrary are superficial
One thing I've found in reading skeptic criticisms of climate science is that they're consistently superficial. For example, the criticisms of James Hansen's 1988 global warming projections never go beyond "he was wrong", when in reality it's important to evaluate what caused the discrepancy between his projections and actual climate changes, and what we can learn from this. And those who argue that "it's the Sun" fail to comprehend that we understand the major mechanisms by which the Sun influences the global climate, and that they cannot explain the current global warming trend. And those who argue "it's just a natural cycle" can never seem to identify exactly which natural cycle can explain the current warming, nor can they explain how our understanding of the fundamental climate physics is wrong.
There are legitimate unresolved questions
Much ado is made out of the expression "the science is settled." My personal opinion is that the science is settled in terms of knowing that the planet is warming dangerously rapidly, and that humans are the dominant cause.
There are certainly unresolved issues. There's a big difference between a 2°C and a 4.5°C warming for a doubling of atmospheric CO2, and it's an important question to resolve, because we need to know how fast the planet will warm in order to know how fast we need to reduce our greenhouse gas emissions. There are significant uncertainties in some feedbacks which play into this question. For example, will clouds act as a net positive feedback (by trapping more heat, causing more warming) or negative feedback (by reflecting more sunlight, causing a cooling effect) as the planet continues to warm?
These are the sorts of questions we should be debating, and the issues that most climate scientists are investigating. Unfortunately there is a large segment of the population which is determined to continue arguing the resolved questions for which the science has already been settled. And when climate scientists are forced to respond to the constant propagation of misinformation on these settled issues, it just detracts from our investigation of the legitimate, unresolved, important questions.
The Big Picture
The big picture is that we know the planet is warming, humans are causing it, there is a substantial risk to continuing on our current path, but we don't know exactly how large the risk is. However, uncertainty regarding the magnitude of the risk is not an excuse to ignore it. We also know that if we continue on a business-as-usual path, the risk of catastrophic consequences is very high. In fact, the larger the uncertainty, the greater the potential for the exceptionally high risk scenario to become reality. We need to continue to decrease the uncertainty, but it's also critical to acknowledge what we know and what questions have been resolved, and that taking no action is not an option.
1. MattJ at 09:37 AM on 24 September, 2010Overall, I think this is an excellent article. But there is still room for improvements in a few spots. The split infinitive, for example, has to go.
Now don't get me wrong: I am not one of those sticklers who believes that every split infinitive is wrong. But THIS one really grates on my ears! I am referring to:
"It's important to every so often take a step back and see how all of those trees comprise the forest as a whole."
While we are fixing the split infinitive, another slight change of wording also makes a marked improvement. I suggest:
"It's important to take a step back every now and then to see how all of those trees form the forest as a whole."
A more substantial point: I -wish- it were as easy as simply asserting, that falsification "would require that our fundamental understanding of physics be wrong, because that's what the theory is based on."
If it were that simple, I doubt that Freeman Dyson would still be objecting to the evidence. And indeed, there is a lot of data collection and interpretation added on top of that "fundamental understanding of physics" to reach the conclusion.
As long as such a prominent physicist as Dyson objects, we cannot expect to get very far by claiming "the theory is based on our fundamental understanding of physics".
Now don't get me wrong, I do not agree with Dyson, and am I mystified and disappointed that he objects. But I do share at least a little of his skepticism concerning the models. It really IS hard to know if the model is correct. Especially when the rebuttal on this very website does not even address the objections Dyson raised: it says nothing about whether or not the new models still rely on 'fudge factors', whether or not they now take into account dust and clouds, etc.
IOW: both this article and that could use some strengthening in similar ways. But this one is already very good, and needs little more to reach perfection -- especially if the other is strengthened as well.
2. MattJ at 09:38 AM on 24 September, 2010BTW: I suppose I should add: if the models still rely on "fudge factors", then the claim that the conclusion is based on "our fundamental understanding of physics" simply does not hold water.
3. Rob Honeycutt at 09:39 AM on 24 September, 2010
Nice work Dana! This puts everything nicely into perspective.
I've wondered about creating a list of different aspects of climate change and putting them into categories in a simple graphic like: 1) Basic physics 2) Settled science 3) Observations 4) New research 5) Uncertainties (or something like that).
I think the average person tends to think of science as being black and white. It either is or it isn't. Good guys and bad guys. Us and them. Etc. And I know science is just not about absolutes. If there were a way to help people understand this basic aspect of climate it might go a long way toward opening some eyes and changing some minds.
4. doug_bostrom at 10:20 AM on 24 September, 2010Nice post!
Oftentimes we get bogged down discussing one of the many pieces of evidence behind man-made global warming, and in the process we can't see the forest for the trees.
Using another optical analogy, no depth of field.
5. scaddenp at 10:39 AM on 24 September, 2010MattJ - the question about model should refer to Models arent reliableargument.
But yes, models most certainly do take into account clouds and aerosols. The closest thing to "fudge factors" would be parameterizations - empirical equations that relate some variable response to inputs. (eg evaporation as response to sea-temp, wind etc). However, it is important to note that the "tuning" of empirical determinations match a specific variable to factors affecting it, NOT to fiddling knobs so that you match observed climate to model. Have a look at this FAQ for example. Further questions to appropriate argument (or ask the modellers themselves).
6. huntjanin at 15:26 PM on 24 September, 2010If I may pose a heretical question - and no offense meant - valuable as these introductory-level posts may be, wouldn't it be better for our expert authors to break some new ground, e.g. by undertaking new research or having new insights, rather than reinventing the wheel (that is, by restating well-known facts in simple terms)?
7. cruzn246 at 17:39 PM on 24 September, 2010Blah, blah, blah. The claim that man is responsible for virtually all warming is pure speculation. To say that is to assume that temperatures would have basically stayed the same over this whole period. Temperatures have not stayed static for any thirty year period ever.
8. adelady at 18:10 PM on 24 September, 2010C'mon Hunt. Do you really expect the average reader of the sports pages to dive into the fiercely technical waters at Real Climate or Science of Doom?
The whole objective of John's project of 1) identify a single argument then 2) describe the scientific background at 3 levels from simple through to full-bore science essay is designed to allow people who get stuck in an argument with a doubter of the science to back up their points with accurate material - pitched at the right level.
It's not the writers who are reinventing the wheel, it's the conversational, opinionated know-nothings who revive and recycle the same old talking points.
9. bverheggen at 18:19 PM on 24 September, 2010Very good post.
Small addition:
Where you write"In fact we expect human greenhouse gas emissions to cause more warming than we've thus far seen, due to the thermal inertia of the oceans (the time it takes to heat them)."
Aerosol cooling is another important factor that we haven't yet seen the full amount of warming that one would expect from GHG emissions. See eg Ramanathan and Feng (2009) http://www-ramanathan.ucsd.edu/publications/Ram-&-Feng-ae43-37_2009.pdf or Raes and Seinfeld short piece in AE last year.
10. CBDunkerson at 18:26 PM on 24 September, 2010cruzn246, no temperatures have not stayed completely static in any 30 year (or 30 minute) period ever. However, they have also never shot up a degree C in a hundred year period without a specific cause. In this case, the cause is us.
11. Dan Olner at 18:56 PM on 24 September, 2010Nice article. One criticism:
Quote: "Sometimes people ask 'what would it take to falsify the man-made global warming theory?'. Well, basically it would require that our fundamental understanding of physics be wrong, because that's what the theory is based on."
I think people asking that question - 'what would it take to falsify the man-made global warming theory?' - are making an ostensibly reasonable request, since falsification is one way of demarcating scientific from non-scientific theories. But usually it's used by denialists to muddy the waters and claim that climate science is not falsifiable and thus not 'proper science', because it proposes no theories or statements that are falsifiable. Here's a UK libertarian example.
Here's my philosophy of science 101 take on this - would love to hear better informed views. "All swans are white" is a falsifiable theory; if you find a black swan, theory falsified. In the same way, Einstein's theory of relativity is falsifiable - Eddington took photos of an eclipsed sun to measure the predicted impact of gravity on light from a distant star. The theory wasn't falsified - but in principle, it is. That's a criterion for good science - unlike, say, "George Bush is a 12 foot shapeshifting lizard from another dimension". "But he looks human." "Exactly."
AGW theory appears unfalsifiable because - it would seem - we need some future date to arrive before the theory can be falsified. It's quite a nice trick: it does appear at first glance that we have to wait for some point in the future to falsify climate theory - and, of course, if the climate does warm, that only confirms the theory, it doesn't falsify it.
They're wrong, though. Surprise surprise. Two ways they're wrong: first, if AGW won't be falsifiable until some point in the future, that ALSO means anti-AGW hypotheses are equally unfalsifiable - if they require us to wait for the future to find out. (Actually, of course, AGW theory does make future, falsifiable predictions, but let's put that aside for the moment.)
So the next question is, do we need to wait for the future before we can have any faith in climate science? No - there are supporting pillars that are falsifiable. You can come up with plenty of null hypotheses: for example, the earth isn't warming. To turn that round, "The
earth is warming" is entirely falsifiable, in principle. Same as the theory of relativity, it just hasn't been falsified - and likely won't be. Clearly, the null hypothesis - say, "the earth hasn't warmed since the 1950s" has been. How about "humans don't cause global warming?" Well, it would need breaking down a bit, but that's easy enough: "co2 doesn't cause atmospheric warming" and "humans aren't putting co2 into the atmosphere" are trivial to falsify.
So again, it's just one of those lovely, sciencey-sounding things that 'skeptics' like, but that actually supports their argument not at all.
12. Dan Olner at 19:11 PM on 24 September, 2010Just to add: good theories carry on standing up against attempts to falsify -here's a story I just read where Einstein's work once again survives. As they say, "our results agree with Einstein's theory – we weren't expecting any discrepancies and we didn't find any."
13. Dan Olner at 19:14 PM on 24 September, 2010Gah! Sorry, should have added this before: what's most perverse and enraging about the denialosphere is that no falsifiable theories are ever proposed - or when they are, and they're falsified, they just duck and dodge. And then some have the temerity to accuse climate scientists of being unscientific? Graaah.
14. Alexandre at 21:14 PM on 24 September, 2010Dan Olner #11
Many things could falsify the "AGW theory". Less downward longwave radiation in the last few decades, for example. Or more OLR with some corresponding other forcing that would justify it in quantity.
That would mean all those extra GHG in the atmosphere are not having an effect. Which would mean well-established theories like Beer-Lambert Law and Planck Law would be wrong (they are actually so well established that they deserve the status of "laws"of physics).
That's why dana said that "our fundamental understanding of physics [would be] be wrong".
15. Craig Allen at 21:40 PM on 24 September, 2010Hey John, Dan Olner's assertion that greenhouse gas induced warming is not a falsifiable theory and therefore not science is a 'skeptic' argument for which you don't have a refutation! I've seen it used a few times here and there, so perhaps it needs one.
Engage your brain Dan. I'm sure you can think of a few ways to falsify AGW theory if you try. For example if any of the phenomenon in John's Ten fingerprints of global warming post were not observed to be occurring, then that would constitute evidence that something was amiss with the theory.
16. Craig Allen at 21:45 PM on 24 September, 2010Sorry Dan, I mouthed off without reading your post properly, and instead made that assumption based on Alexandre's response. I see that you are not in fact making the assertion that AGW theory is not falsifiable.
17. huntjanin at 21:49 PM on 24 September, 2010Thanks, Adelady, for your good comment (#8).
My doubts about the wisdom of this project will of course vanish immediately if someone
can assure me that one or more of these basic posts has had some positive effect on a denier.
18. kdkd at 22:10 PM on 24 September, 2010huntjanin:
Dont' just think about turning deniers. Also think about preventing soft "believers" (yuck) from turning.
19. Dan Olner at 23:16 PM on 24 September, 2010huntjanin: "My doubts about the wisdom of this project will of course vanish immediately if someone can assure me that one or more of these basic posts has had some positive effect on a denier."
Related to that, just been watching the late Steve Schneider tackle a room of sceptics. It's a fantastic insight into a range of sceptic mindsets that you just can't get from the interwebs. A number of them clearly have the wherewithall - given the right information and time - to piece together the story. They've just been exposed to some misleading information. But one or two - the doctor near the start - ask Schneider for an explanation on something, get a really clear explanation, and then repeatedly shout him down saying he hasn't answered the question.
The heartening thing seems to be, he's the rarity, not the norm. The question then is, what's the ratio of rational to irrational on the web? And are people that come here a self-selecting audience?
Oh - here's a link to the video.
Clearly, it wasn't hard to gather a doubting audience in one place, willing to listen to a prominent scientist. I suspect blog science suffers far more from ghettoisation.
Maybe the answer is that skepticalscience.com and other sites are needed, but until the information here gets out into meatworld public forums, its impact may be lessened.
20. Michael Searcy at 23:23 PM on 24 September, 2010Dr. Schneider does a great job addressing the falsifiability of climate science in a lecture he gave back in February which has been given the title, "Climate Change: Is the Science 'Settled'?"
In summary he states...
"Climate system science, like others, is really a preponderance of evidence based outcome. It is not falsifiable. Not in the short run....We do not falsify by single experiments. We falsify on the basis of accumulated numbers of papers and number of bits of information."
21. shdwsnlite at 23:28 PM on 24 September, 2010First i want to say this is an excellent post.
@huntjanin... When i am arguing with someone about AGW I am not focused on convincing them as they are usually too invested in their denial. What I try to keep in mind is the possible audience that is listening to or reading the comments. Those are the ones I am trying to inform by offering civil, reasoned, and fact based replies.
I have used this site as a resource for some time now. The primary reason is to better
educate myself which with this 50+ year old brain is a struggle at times. High school and college science was a very long time ago. Thanks to John and all the contributors who devote so much time and energy to keeping this a much needed model of civil discourse and learning.
22. tobyjoyce at 23:33 PM on 24 September, 2010@Dan Older, #11,
Excursions in to the philosophy are usually considered OT, but here is my 2c.
"Falsifiability" is a good criterion to demarcate science from non-science. In that respect, it resembles Occam's Razor or Hume's Fork. However, it is not a good criterion to assess a branch of science, as climate science has become.
Scientific theories are usually composite and stated as generally as possible. A black swan may falsify the simple hypothesis "All swans or white" but not the more general hypothesis "Most swans are white" or even "Some swans are white". With inductive logic, it is often easier to modify the hypothesis than reject it.
The difficulty of "falsifying" a science is best illustrated by a story from physics. At the start of the 19th century, astronomers found that the planet Uranus was not appearing as predicted by Newton's Laws. Did they therefore stop using Newton's Laws? Of course not - the laws were too accurate in other places to drop them completely. Instead, two astronomers (Adams and Leverrrier) used the discrepancies to propose that there was another planet beyond Uranus. There prediction was verified when the planet Neptune was observed in 1846, exactly where it was predicted to be.
Fine, a triumph of science. Bur later in the century discrepancies were found in the orbit of Mercury, and again the existence of another planet was proposed (called Vulcan). But Vulcan was never observed, and the discrepancy was later correctly explained by Einstein's Theory of Relativity. However, in the interim, Newton's Laws had continued to be used with gusto.
So "falsifiability" is too simple a criterion to judge a large and expansive scientific programme. It may work when a science is in its infancy - the best example I can think of is Fred Hoyle's Steady State Theory of the cosmos, which was slain by the simple observation of the microwave remnants of the Big Bang. But the Big Bang theory iteslf is now so complex and composite it is doubtful if a single observation could dethrone it overnight.
The reference you gave was somewhat confused - it referred to a science discussion in 1961 as if it had contemporary relevance, and provided no instances where climate scientists were making predictions that were not falsifiable. I find deniers take simple lacunae in the theory of AGW and immediately jump up and down saying "Falsified! Falsified!".
PS Just read Michael Searcy's comment #20... Dr Schneider states it much more succinctly than me!
23. doug_bostrom at 23:56 PM on 24 September, 2010If there is a single ongoing experiment offering the best hope of crisply falsifying the notion of anthropogenic climate change, perhaps it's night time surface atmospheric temperatures? This is sampled with ancient, thoroughly understood instrumentation, comprehensively deployed, no confounding factors if the simplest and most transparent data conditioning is
A reasonable person might conclude that if night time temperatures were refusing to behave "properly," we may have a wee problem with the notion of AGW. As it stands, overnight temperatures are behaving exactly as we'd expect; the behavioral details of the decline of diurnal surface temperature variation seem impossible to explain by other means.
Perhaps it's the very simplicity of this message of surface temperature records which compels "skeptics" to discard surface temperature records as false. Failing a scientific explanation, speculations about fraud or incompetence are all that's left to discount the first, easiest, most bulky and unequivocal evidence of AGW.
Ironically, past such simple matters as diurnal temperatures, "skeptics" seem to be becoming lost in the myriad of complicated knock-on findings of researchers delving into climate change. The more evidence they demand, the less perfectly atomic and hermetic new evidence will be; ignoring the obvious means dealing with the arcane.
Huntjanin, for my part I don't think any but the very softest and least committed "skeptic" will be swayed by -any- argument based on science. This "debate" is not really about science at all. For helping ordinary people who are curious about this matter and want to know what all the fuss is about, offering simplified explanations with pointers to details seems a worthwhile exercise.
Constructing these basic explanations is a fascinating exercise in itself, a matter of teasing essential concepts out of things often very complicated.
24. Ken Lambert at 00:32 AM on 25 September, 2010Adelady #8
"It's not the writers who are reinventing the wheel, it's the conversational, opinionated know-nothings who revive and recycle the same old talking points."
What is it with something about 'she who is without sin casting the first stone?'
Presumably in your view only deniers and sceptics (why not call them tanks?) have the same old talking points.
As if the age of a point has anything to do with its value.
Old talking points arise because they might be uncertain, difficult, controversial and not resolved - like the real contribution of CO2GHG to warming, WV and CO2 interaction, OHC measurement, etc etc.
BTW who is dana1981 anyway - he/she seems to be recycling lots of 'old talking points' lately.
25. paulm at 00:46 AM on 25 September, 2010Nice post. I have to add that I think the conclusion can be tightened up a bit.
We may not know the exact risk but we have a pretty good idea what the ballpark figures are in terms of risk management. It's not difficult when we can clearly see that continued AGG emissions will more than likely result in extreme GW, which will most likely result in a severe mass extinction event.
It clearly will most likely result in to collapse of modern civilization and very probably the reduction of the human species to very low numbers. There is also a possibility of the run away GH effect which would annihilate life.
So the statement "uncertainty regarding the magnitude of the risk" in the conclusion is a bit miss leading.
26. Daniel Bailey at 00:48 AM on 25 September, 2010Re: Ken Lambert (24)
"What is it with something about 'she who is without sin casting the first stone?'"
Actually, it's "If any one of you is without sin, let him be the first to throw a stone at her." Remember, the society of the day was patriarchal, so the gender of the expression is male. (but perhaps you were adapting it to adelady?)
"Presumably in your view only deniers and sceptics (why not call them tanks?) have the same old talking points."
Those same old talking points you reference are the ones whose science the "deniers and sceptics" fail time and again to overcome.
"As if the age of a point has anything to do with its value."
Well-spoken, sir.
The Yooper
27. paulm at 01:05 AM on 25 September, 2010A good paper on why a large portions of the general public, journalists, and policy makers dont get the "...scale of the problem and the urgency of required action"is :
What psychology can teach us about our response to climate changehttp://www.guardian.co.uk/environment/blog/2010/sep/23/climate-change-psychology-response-scepticism
"Simply presenting the facts and figures about global warming has failed to convince large portions of the general public, journalists, and policy makers about the scale of the problem and the urgency of required action. From a psychologist's perspective this disconnect is not surprising."
28. doug_bostrom at 02:06 AM on 25 September, 2010Following from PaulM's comment, this is a useful article:
The Psychology of Global Warming (AMS, full text pdf)
Leaving aside that little group tagged by Leiserowitz as the "dismissive," if we take heed of what we've learned of how people think, our communications actually can be made more effective, more robust in the face of industrial PR.
29. dana1981 at 02:21 AM on 25 September, 2010cruzn246 #7 - I suggest you actually click the links and learn something. There's a pretty darn big difference between scientific evidence and "pure speculation."
bverheggen #9 - valid point, I may add a bit on aerosols. I wrote a rebuttal on the subject recently which I didn't link in this article.
Dan Olner #11 - there's a difference between what it would take for AGW to be wrong (our understanding of physics would have to be wrong) and what it would take to disprove AGW. To disprove the theory, just demonstrate that the planet is not warming or climate is not changing as it predicts. I recommend you click the 'fingerprints' link in the article to see what I mean.
Ken Lambert #24 - perhaps you're unfamiliar with Skeptical Science. The purpose of the site is to debunk false skeptic arguments with scientific evidence.
paulm #25 - I'll consider rewording the conclusion a bit.
30. Stephen Baines at 07:21 AM on 25 September, 2010Dana, I think this is a great post. I'm forwarding it to my relatively climate naive sister so she has a good entry point to the amazing resources on this web site.
One thing regarding falsification. (This particular line of argument from deniers drives me completely batty!) I would argue that it's more correct to say that ober 50 years AGW has been repeatedly subject to intense attempts at falsification by skeptical scientist and it has passed those tests repeatedly, so that now it would take a truly astonishing series of events/findings to shake the hard won belief in it that most now scientists have.
The way it's put now is strictly true, but it sounds a little condescending for those not very aware of those physical principles you speak of (I presume this level of explanation is targeted at such people). It reads a bit like "us smart people thought this up using theories that you can't possibly understand, so don't question it." That plays perfectly into the whole anti-elitism meme that lurks beneathe this debate. It also somewhat undersells the great body of observational data that does not rely on those physical principles.
Perhaps some way for people to understand how they depend on those physical principles in their every day lives would help bring it home too.
31. PeteM at 07:27 AM on 25 September, 2010(I don't claim to be a specialist in this area but I do have a science degree )
When talking with friends and colleagues who don't have a science background I tend to use the following way of describing what a few degrees centigrade rise really means ...
"The numbers one ,two , three and four don't sound much. Two centimeters seems a small number . However to understand a two degrees (c) rise in temperature think what you would say if I suggested you lift (by yourself) Mount Everest by two centimeters - it's only a small number so it should be easy . Now think about how much disruption must have occured to make a one degree centigrate rise to the temperature of the Earth .... and then project what the consequences could be of a two or three degree rise - a small number can mask gigantic changes.... This is the impact of fossil fuels on the green house effect "
32. Tarcisio José D'Avila at 07:50 AM on 25 September, 2010Retification...Do you ever wonder, "Is the thermostat of nature" is not stuck?
If it is stalled antropogenic actions has great potential to be the cause of all this damage.I do not believe that acts falcification of data.
33. Tom Dayton at 08:20 AM on 25 September, 2010Tarcisio, please rephrase your comment. I don't understand your point.
34. Tarcisio José D'Avila at 09:13 AM on 25 September, 2010Tom #33I go wrait with may poor english escuseme...If the thermostat of the climate is brook or is out of range, the global warm has great potential of be antropogenic. And in this case the science is rigth.Only the target of resershing is bad. It's look to the fingeprint only.
35. Daniel Bailey at 12:15 PM on 25 September, 2010Re: Tarcisio José D'Avila (32,34) and Tom Dayton (33)
If I understand Tarcisio José D'Avila correctly, he is postulating the existence of a broken "climate thermostat". Broken, because it is not correcting for the actions of man's fossil fuel CO2 emissions. An iteration of the Gaiahypothesis, I believe.
He believes the science of anthropogenic warming is right, but that it only is warming because the thermostat itself is broken. Or something like that.
If I've misunderstood, I apologize.
The Yooper
36. KR at 15:07 PM on 25 September, 2010Tariscio - I would love to read your comments, but find your translations difficult to follow.
I would suggest including both your native language (Spanish?) in appropriate detail, and using Google translate to produce an additional English version. Many of us can read or at least puzzle out other languages.
37. cruzn246 at 16:28 PM on 25 September, 2010Well Dunkerson, you think it is all us? I mean think about it. How can they claim that a change in temperature is completely or even mostly the responsibility of man when we are not even at the point when we truly know what makes our temperatures change and how much they change anyway. We have never been around at this point in a glacial period, so who are we to know what happens when it gets to this point?
38. RSVP at 17:07 PM on 25 September, 2010MattJ #1"I do not agree with Dyson, and am I mystified and disappointed that he objects."
As per your comment, his interview on YouTube may help. To see, just google his name, etc. I dont think he is saying global warming is not real as much that stratospheric cooling might be a bigger problem.
Similarly, while he plays down the imperative to reduce fossil fuels (towards the end of the video), in his book, Disturbing the Universe, he pretty much writes that humanity missed its opportunity in the sixties to go nuclear due to unwarranted alarmism, such that he was more optimistic about the ability to build safer reactors.
39. cruzn246 at 17:14 PM on 25 September, 2010Anyone seen this?
40. Dappledwater at 18:12 PM on 25 September, 2010Cruzn @ 39 - is that by that German school teacher?.
41. CBDunkerson at 19:09 PM on 25 September, 2010Yes, three years ago Beck picked a fight with a dead man... and lost. Apparently this nonsense is coming back up again because Beck died this week.
In brief, decades ago Guy Stewart Callendar took atmospheric CO2 readings by various people all over the world (see the list of name at the bottom of Beck's chart) and analyzed them in an effort to determine if there was any trend in CO2 levels. He found that alot of the readings showed a steadily increasing trend line, but there were also alot of outliers... all on the high side and all downwind of major industrial centers. He therefor reasoned that these high readings were being caused by recent emissions that had not yet mixed through the atmosphere and excluded them.
Beck, forty years after Callendar's death, called this 'scientific fraud' and insisted that the only proper way to do a scientific study is to include ALL of the data... even that which is clearly erroneous. His results, based on including readings from right outside coal plants (which were, of course, one of the places such readings were taken) yielded the graph above... further skewed by the fact that there were very few readings available for the early part of the chart and almost all of them were from industrial regions.
Of course Beck's paper was provably nonsense the day it came out. Multiple stations around the world have long since validated Callendar's results and satellite analysis has also confirmed it in recent years.
There is no greater proof of the deficiency of the 'skeptic' position than their insistence on holding fast to pure fiction.
42. CBDunkerson at 19:11 PM on 25 September, 2010PS: I should have also mentioned ice core CO2 records... direct readings of CO2 levels in air bubbles. Which ALSO verified Callendar's results and made Beck's analysis obviously false before he even published it.
43. muoncounter at 22:32 PM on 25 September, 2010#41: "there were also alot of outliers... all on the high side and all downwind of major industrial centers."
Isn't that direct experimental proof that increased atmospheric CO2 is anthropogenic?
44. CBDunkerson at 22:56 PM on 25 September, 2010muoncounter, that's an interesting point. We hear so much about how human CO2 emissions are tiny compared to natural emissions, but when looked at geographically there is a very clear human signal in the CO2 satellite maps (and the earlier data). Presumably this is because natural emissions are spread out around the globe and balanced by natural sinks in nearly equal measure. However, human emissions are comparatively very concentrated... and the areas with the greatest emissions (cities) also have the most minimal carbon sinks (because there are few plants).
Still, this does NOT (by itself) prove global atmospheric CO2 increases are due to humans. If global carbon sinks were able to absorb the extra amount we'd see locally elevated CO2 from humans, but the long term trend would be flat. Since we see locally elevated amounts AND a positive trend it is clear that carbon sinks are not able to handle all of the additional CO2.
45. muoncounter at 23:10 PM on 25 September, 201044: "Since we see locally elevated amounts AND a positive trend it is clear that carbon sinks are not able to handle all of the additional CO2. "
Agreed. But if elevated amounts of atmospheric CO2 are in close context with power plants, urban areas, etc, on the local level, it would be completely illogical to insist that the global total fossil fuel emissions does not result in increased global atmospheric CO2.
46. cruzn246 at 02:07 AM on 26 September, 2010So how do you all explain the big drops in the CO2 chart from Beck? Did folks quit burning coal in those years? did winds mysteriously change directions for years?
BTW, Ice cores are not that accurate. The most recent do not show the so called increase we are seeing.
Can someone tell me how warm it would be if no CO2 was in the atmosphere?
47. doug_bostrom at 02:18 AM on 26 September, 2010"...if no CO2 was in the atmosphere?"
Is anybody going to rise to that bait? Take the refusal to acknowledge CBDunkerson's remarks concerning Beck as a hint as to whether the little sardine is worth biting.
48. archiesteel at 02:21 AM on 26 September, 2010@cruzn246, first, please answer this simple question: are you here to learn, or simply repeat denier arguments you've read elsewhere? Because if it's the latter, then kindly abstain from it. Instead, look up those arguments in the list compiled on this site to get an accurate rebuttal. Thanks.
"So how do you all explain the big drops in the CO2 chart from Beck?"
Beck's chart is inaccurate, so who knows what the drops and bump means. For example, if Beck's primary sources were in Germany, then it would make sense for the big bump during WWII, as the country's industry went into overdrive.
In any case, the graph (and the paper it came from) was thoroughly debunked.
"BTW, Ice cores are not that accurate. The most recent do not show the so called increase we are seeing."
Perhaps not (I'd have to check), but the older one disprove Beck's graph.
"Can someone tell me how warm it would be if no CO2 was in the atmosphere?"
Off-hand, I remember it being something akin to 30C, but I could be wrong. What's that got to do with it?
49. archiesteel at 02:24 AM on 26 September, 2010...sorry, I meant "30C colder".
50. cruzn246 at 02:26 AM on 26 September, 2010The whole thing about CO2 just leaves me baffled. Of course it is explained that CO2 lags for whatever reason when a warmup occurs. OK, so after that it becomes a driver. So why the heck can you never go anywhere in the temperature history and find one stinking time that temperature peaked after CO2 peaked? I mean if it's driving then.........Face it people, the big greenhouse gas here is water vapor.
I am not saying it is a zero factor, but till we really see some temperatures out of the norm, which we are not close to seeing, I can't buy this notion about CO2 causing some big change here. We are well within norms. We are still in what has been a relatively warm period called the Holocene, and the simple fact is that we will probably see higher temps then this before this whole climate system flips. It happened before and it will happen again. And CO2 has little or nothing to do with it. it is a minor player in the whole climate system. Greenouse gases allow us to trap heat, but they are not the big players in climate change. The whole system is so complex we barley know how it works but the balance of solar factors, albedo, and ocean temperatures and currents are all bigger players. Anyone who knows anything about our glacial climatology should know that we are bound to stay warm until we see a radical change in ocean currents. That is probably the big tripper in the system. When that gulf stream doesn't flow to Europe anymore, usually about the time FL is mostly water covered, things flip.
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The Big PictureOftentimes we get bogged down discussing one of the many pieces of evidence behind man-made global warming, and in the process we can't see the forest for the trees. It's important to every so often take a step back and see how all of those trees comprise the forest as a whole. Skeptical Science provides an invaluable resource for examining each individual piece of climate evidence, so let's make use of these individual pieces to see how they form the big picture.
The Earth is warming
We know the planet is warming from surface temperature stations and satellites measuring the temperature of the Earth's surface and lower atmosphere. We also have various tools which have measured the warming of the Earth's oceans. Satellites have measured anenergy imbalance at the top of the Earth's atmosphere. Glaciers, sea ice, and ice sheetsare all receding. Sea levels are rising. Spring is arriving sooner each year. There's simply no doubt - the planet is warming.
And yes, the warming is continuing. The 2000s were hotter than the 1990s, which were hotter than the 1980s, which were hotter than the 1970s. 2010 is on pace to be at least in the top 3 hottest calendar years on record. In fact, the 12-month running average global temperature broke the record 3 times in 2010, according to NASA GISS data. Sea levels are still rising, ice is still receding, spring is still coming earlier, there's still a planetary energy imbalance, etc. etc. Contrary to what some would like us to believe, the planet has not magically stopped warming.
Humans are causing this warming
There is overwhelming evidence that humans are the dominant cause of this warming, mainly due to our greenhouse gas emissions. Based on fundamental physics and math, we can quantify the amount of warming human activity is causing, and verify that we're responsible for essentially all of the global warming over the past 3 decades. In fact we expect human greenhouse gas emissions to cause more warming than we've thus far seen, due to the thermal inertia of the oceans (the time it takes to heat them). Human aerosol emissions are also offsetting a significant amount of the warming by causing global dimming.
There are numerous 'fingerprints' which we would expect to see from an increased greenhouse effect (i.e. more warming at night, at higher latitudes, upper atmosphere cooling) that we have indeed observed. Climate models have projected the ensuing global warming to a high level of accuracy, verifying that we have a good understanding of the fundamental physics behind climate change.
Sometimes people ask "what would it take to falsify the man-made global warming theory?". Well, basically it would require that our fundamental understanding of physics be wrong, because that's what the theory is based on. This fundamental physics has been scrutinized through scientific experiments for decades to centuries.
The warming will continue
We also know that if we continue to emit large amounts of greenhouse gases, the planet will continue to warm. We know that the climate sensitivity to a doubling of atmospheric CO2 from the pre-industrial level of 280 parts per million by volume (ppmv) to 560 ppmv (we're currently at 390 ppmv) will cause 2–4.5°C of warming. And we're headed for 560 ppmv in the mid-to-late 21st century if we continue business-as-usual emissions.
There will be some positive results of this continued warming. For example, an open Northwest Passage, enhanced growth for some plants and improved agriculture at high latitudes (though this will require use of more fertilizers), etc. However, the negatives will almost certainly outweigh the positives, by a long shot. We're talking decreased biodiversity, water shortages, increasing heat waves (both in frequency and intensity), decreased crop yields due to these impacts, damage to infrastructure, displacement of millions of people, etc.
Arguments to the contrary are superficial
One thing I've found in reading skeptic criticisms of climate science is that they're consistently superficial. For example, the criticisms of James Hansen's 1988 global warming projections never go beyond "he was wrong", when in reality it's important to evaluate what caused the discrepancy between his projections and actual climate changes, and what we can learn from this. And those who argue that "it's the Sun" fail to comprehend that we understand the major mechanisms by which the Sun influences the global climate, and that they cannot explain the current global warming trend. And those who argue "it's just a natural cycle" can never seem to identify exactly which natural cycle can explain the current warming, nor can they explain how our understanding of the fundamental climate physics is wrong.
There are legitimate unresolved questions
Much ado is made out of the expression "the science is settled." My personal opinion is that the science is settled in terms of knowing that the planet is warming dangerously rapidly, and that humans are the dominant cause.
There are certainly unresolved issues. There's a big difference between a 2°C and a 4.5°C warming for a doubling of atmospheric CO2, and it's an important question to resolve, because we need to know how fast the planet will warm in order to know how fast we need to reduce our greenhouse gas emissions. There are significant uncertainties in some feedbacks which play into this question. For example, will clouds act as a net positive feedback (by trapping more heat, causing more warming) or negative feedback (by reflecting more sunlight, causing a cooling effect) as the planet continues to warm?
These are the sorts of questions we should be debating, and the issues that most climate scientists are investigating. Unfortunately there is a large segment of the population which is determined to continue arguing the resolved questions for which the science has already been settled. And when climate scientists are forced to respond to the constant propagation of misinformation on these settled issues, it just detracts from our investigation of the legitimate, unresolved, important questions.
The Big Picture
The big picture is that we know the planet is warming, humans are causing it, there is a substantial risk to continuing on our current path, but we don't know exactly how large the risk is. However, uncertainty regarding the magnitude of the risk is not an excuse to ignore it. We also know that if we continue on a business-as-usual path, the risk of catastrophic consequences is very high. In fact, the larger the uncertainty, the greater the potential for the exceptionally high risk scenario to become reality. We need to continue to decrease the uncertainty, but it's also critical to acknowledge what we know and what questions have been resolved, and that taking no action is not an option.
51. cruzn246 at 02:28 AM on 26 September, 201030C colder? Are you nuts? No frickin way. Wherever you got that from is crazy.
52. CBDunkerson at 02:29 AM on 26 September, 2010cruzn246 #46, the 'big drops' in Beck's chart are actually returns to more accurate results. The anomalous peaks exist only because he used fragmentary records rather than a consistent series. This wasn't a matter of taking regular readings at fixed sites. Callendar gathered any and all old historical measurements he could find and Beck re-used those same records. The difference is that when Callendar found anomalously high readings in individual years / particular areas he discarded them as corrupted data while Beck decided these were indicative of a global trend which somehow magically didn't appear in the other readings.
Seriously, your continued insistence on treating Beck as anything but a bad joke is a classic example of why there is so much disdain for 'skeptics'... there is NOTHING skeptical about it. Ice core records, sediment proxies, modern CO2 monitoring stations all over the world, satellite readings, and basic logic ALL say that Beck's analysis is complete nonsense. Yet still you prefer the insane ramblings (and CO2 fluctuating +/- 100 ppm over the course of a mere decade IS insane) of a high school teacher to absolute and irrefutable scientific findings by hundreds of specialists in a half dozen different fields over the course of decades.
As to how warm it would be without CO2. CO2 accounts for about 26% of the 33 C greenhouse warming. That yields about 8.6 C. However, if it were 8.6 C cooler there would also be less water vapor in the air... which would make it cooler still... which would mean more ice cover and thus a higher albedo... which would make it even colder. In short, we can't determine the precise value. However, it is safe to say that most of the planet would be a frozen ball of ice. Maybe a narrow 'temperate' zone around the equator.
53. Tom Dayton at 02:33 AM on 26 September, 2010I have replied to cruzn246 over on the more appropriate thread for further discussion: CO2 measurements are suspect.
Moderator Response: Good point.
For continued wrangling over C02 measurement accuracy, go here: CO2 measurements are suspect
To further discuss sensitivity: A detailed look at climate sensitivity
If you're not familiar with the comments policy here and would like to know why comments swerving deeply into specialist topics will likely vanish after more appropriate threads are pointed out, see Comments Policy
54. muoncounter at 02:35 AM on 26 September, 2010#46: "how do you all explain the big drops in the CO2 chart from Beck?"
Easy. From a presentation (not published?) by Massen and Beck 2006: The historic measurements have horrible standard deviations. See Fig 10: 398+/-62 ppm, Fig 11: 327+/-23ppm, Fig 12: 339+/-33.
55. CBDunkerson at 02:38 AM on 26 September, 2010cruzn246 #50: "So why the heck can you never go anywhere in the temperature history and find one stinking time that temperature peaked after CO2 peaked?"
There ARE cases where temperature peaked after CO2 did. For instance...now, various flood basalt incidents, the snowball Earth scenario ~650 million years ago, et cetera.
56. Daniel Bailey at 02:38 AM on 26 September, 2010Re: cruzn246 (46), doug_bostrom (47)
OK, I'll take my turn at the plow, Doug.
"Can someone tell me how warm it would be if no CO2 was in the atmosphere?"
To even ask this questions is telling as to your state of awareness of the science. But let's pretend you have honestly asked that question. Here's a quick, quasi-sciency answer:
If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth, it would have an expected blackbody temperature of 5.3 °C. However, since the Earth reflects about 30%[4] (or 28%[5]) of the incoming sunlight, the planet's actual blackbody temperature is about -18 or -19 °C [6][7], about 33°C below the actual surface temperature of about 14 °C or 15 °C.[8] The mechanism that produces this difference between the actual temperature and the blackbody temperature is due to the atmosphere and is known as the greenhouse effect.
So, essentially a global average temp of -2 degrees F, or about -18 degrees C. Thus, no liquid water anywhere and no life. All very well understood for over a hundred years.
Water vapor acts to enhance the warming of greenhouse gases, which can then elevate CO2 levels even more, which can then enhance temps even more. This usually dampens itself out over time; temps & CO2 levels eventually reach an equilibrium. These all are quantifiable due to the physics of radiative gases (no computer or fancy GCM's required). It does get a little complicated sometimes, depending upon the rates at which CO2 changes.
But, hey, no one said it would be easy to learn.
BTW, CO2 is the most important of the greenhouse gases, even including water vapor. You really ought to watch this for a clear explanation.
The Yooper
57. archiesteel at 02:42 AM on 26 September, 2010@cruzn246: "The whole thing about CO2 just leaves me baffled."
Clearly, but just because you're ignorant of the science doesn't mean you should assume it's wrong.
"Of course it is explained that CO2 lags for whatever reason when a warmup occurs."
CO2 Lags Temperature
"Face it people, the big greenhouse gas here is water vapor."
We are not adding new water vapor to the atmosphere, but we are adding CO2 that has been sequestered for millions of years.
The current warming is due to rising CO2, which is likely to increase the amount of WV in the atmosphere, thus increasing the warming.
"but till we really see some temperatures out of the norm, which we are not close to seeing"
We are breaking an increasing amount of temperature records, we are at the end of the warmest decade in recorded history, and the increase matches what the climate models predict. What more proof do you want? People's clothes catching on fire when they go out for a stroll? Don't be ridiculous, please.
"We are still in what has been a relatively warm period called the Holocene, and the simple fact is that we will probably see higher temps then this before this whole climate system flips."
Actually, we're past the climate optimum for this interglacial period, so temperatures should be (slowly) going down instead of rising.
"And CO2 has little or nothing to do with it. it is a minor player in the whole climate system. Greenouse gases allow us to trap heat, but they are not the big players in climate change. [...] The whole system is so complex we barley know how it works but the balance of solar factors, albedo, and ocean temperatures and currents are all bigger players."
Science disagrees with you.
"Anyone who knows anything about our glacial climatology should know that we are bound to stay warm until we see a radical change in ocean currents."
Why do you believe you know more than the experts in the field?
Please educate yourself.
58. archiesteel at 02:46 AM on 26 September, 2010@cruzn246: "30C colder? Are you nuts? No frickin way. Wherever you got that from is crazy."
Such brilliant rhetoric has convinced me. *rolleyes*
I'm sorry, cruzn246, I though you were a serious commenter, but now I see you're just a common troll. Mods, can we remove cruzn246's post and this reply? They add nothing to the discussion.
59. cruzn246 at 02:48 AM on 26 September, 2010As to how warm it would be without CO2. CO2 accounts for about 26% of the 33 C greenhouse warming. That yields about 8.6
26% today? How about when CO2 was at 180 or so 10,000 years ago.
Moderator Response: See Does high levels of CO2 in the past contradict the warming effect of CO2?. Discuss the topic on that thread.
We are breaking an increasing amount of temperature records, we are at the end of the warmest decade in recorded history, and the increase matches what the climate models predict. What more proof do you want? People's clothes catching on fire when they go out for a stroll? Don't be ridiculous, please.
Recorded history. Big deal. We know it was warmer than this during the Holocene many times. So we are at the warmest in the last 200 years. That isn't a big enough sample to say warmest ever. Cripes, pull some reality glasses on. These temps are well within norms. So the models got it right. Whooppeee!
Moderator Response: See the argument It's Not Bad.
61. archiesteel at 02:59 AM on 26 September, 2010@cruzn246: "26% today? How about when CO2 was at 180 or so 10,000 years ago."
Temperatures were about 8 degrees colder at that time.
So, 46% less CO2 (roughly half) means 8 degrees colder. That's more than the 3C climate sensitivity currenly estimated, actually, and evidence of positive/negative feedback when CO2 levels change.
62. archiesteel at 03:02 AM on 26 September, 2010@cruzn246: "We know it was warmer than this during the Holocene many times."
Actually, it wasn't (as far as global averages are concerned).
Also, you should put cited text you reply to in quotes, it makes it easier to understand the points you are trying to make.
63. johnd at 03:14 AM on 26 September, 2010CBDunkerson at 19:09 PM, the CO2 levels recorded at the surface stations used in this study Mechanisms for synoptic variations of atmospheric CO2 in NorthAmerica, South America and Europe clearly indicate the huge seasonal variation in CO2 levels which coincides with increased uptake by plants during the growing season.
The annual cycle shows variations of generally 20-40ppm but can be in excess of 50ppm depending on location.
Interestingly even when the stations are located in heavily industrialised regions the same seasonal variation still occurs but with some of the highest annual variations of all the locations sampled, the station at Heidelberg Germany, described as having a fairly strong industrial influence to the east being the prime example with annual variation in excess of 50ppm.
Moderator Response: Wrong thread for continuing this conversation. See the Moderator's Comment on Tom Dayton's comment.
64. johnd at 03:25 AM on 26 September, 2010cruzn246 at 02:26 AM, this review of the most recently published study Fresh water may have cooled North Atlantic putting that "the decrease recorded in the Earth's temperature between the 1940s and 1970s was caused by a sudden cooling of the oceans in the northern hemisphere" may be of interest to you.
Archiesteel"Actually, we're past the climate optimum for this interglacial period, so temperatures should be (slowly) going down instead of rising."
So some think. That is for folks who really don't know what the real tripping point is. Fact is, it is probability ocean currents/sea levels, and when that happens a slow fall is not what you will see. It'll be a very sharp drop. There is some chance we may not warm up fast enough to bring the sea levels up to catch the right Milankovitch cycles, but that is still something we are waiting to see. The ocean current drive may be so strong that it will even overcome what is thought to be the "wrong" time in the Milankovitch cycle. It also may be that we could miss the glacial period if we hold seal levels down for a few more thousand years. Of course that's gonna be hard to do. when you are in the warm cycle, as we are, oceans just seem to keep rising till.......the trip happens.
66. doug_bostrom at 03:37 AM on 26 September, 2010"Tripping point?" "till.......the trip happens?" Are you sure you've got your terminology straight, Cruzn246?
67. Daniel Bailey at 03:41 AM on 26 September, 2010Re: cruzn246
For someone who wants to be a Climatologist, you know very little about the field. or about science or the scientific method. You are telling people here on this thread, with lifetimes of experience and working knowledge in the field, the the science they know (which is itself based on the accumulated lifetimes of study and research of hundreds of thousands of scientists) is wrong. Do you not see a problem with that?
I would suggest, at the very least, going here and follow the links and try to gain a base understanding of what's actually going on in the field.
If you want to learn, first admit you don't know everything. That's a prerequisite.
The Yooper
68. doug_bostrom at 03:56 AM on 26 September, 2010For my part I'm not a researcher studying matters of climate, but I follow the topic fairly closely and that's why I can't help but notice cruzn246's disagreement with vast swathes of established research findings, a sweeping dismissal that is boldly conspicuous. Take a moment to summarize what cruzn246 disagrees with and then ask, "what's the probability 'cruzn246' knows better?" My guess is that he/she will disagree with anything smacking of an attribution of significant climate change to anthropogenic influences.
The big picture, again.
69. johnd at 03:58 AM on 26 September, 2010It's interesting, or perhaps amusing, that this thread wants to take a step back because "often we can't see the forest for the trees". Nothing wrong with that in itself, however given that one theme that consistently plays here is that sceptics don't have just one argument to rebutt AGW but numerous ones, or numerous trees. The response then almost inevitably is that whilst there may be some correlation from the evidence presented, the individual trees, unless there is 100% correlation, then the argument presented fails.
What is apparent from that general treatment of the various arguments presented is a lack of understanding that perhaps the climate, the forest, does not respond to just one dominant driver or tree, in the case of the AGW argument, CO2, but instead responds to numerous drivers that vary in timing and magnitude as to what force, positive or negative, they contribute to the overall nett result.
The tree and forest analogy is very appropriate I feel given the weight given to tree rings as a means of establishing proxy temperatures. Just as many sceptic arguments do not show 100% correlation, nor do all the trees in the forests used to collect tree ring data show 100% correlation, In fact the majority of the trees don't, and it comes down to selecting just a few that show high correlation in order to compile the data sets required.
70. beam me up scotty at 04:15 AM on 26 September, 2010May you live in interesting times.Or"It's better to be a dog in a peaceful time than be a man in a chaotic period" (寧為太平犬，不做亂世人; pinyin: níng wéi tàipíng quǎn, bù zuò luànshì rén
71. cruzn246 at 04:20 AM on 26 September, 2010God, hit me for typos (probability) and hit me for not using the terminology you all use (trip rather than tip). I meant to complete the sentence differently when I used probability, and didn't go back to fix it. I think of the big change in climate like a trip wire.
I disagree with the whole premise because I have never been shown that CO2 is responsible for most of our current warmup. It's that simple. You can throw some sort of "science" at me, but when it flies in the face of the past, not just the recent past, I just don't buy it.
72. cruzn246 at 04:27 AM on 26 September, 2010I do think that when, and if, the climate goes back into glaciation it will be very sudden in the N hemisphere, as far as temperature change is concerned. I think the N hemisphere drives global change. I also think the shutdown of the Gulf stream is the trigger. Will worldwide tamps show the same quick drop. heck no. It'll take time to cool of all that water in the S Hemisphere. But that doesn't mean N Hemisphere tempos will drop slow. They will almost be in a free-fall. I would bet changes on the order of 2C in a century over the N hemisphere would happen easily. I also think that could go on for 500 years or so.
73. CBDunkerson at 04:29 AM on 26 September, 2010cruzn246 #71: "I disagree with the whole premise because I have never been shown that CO2 is responsible for most of our current warmup. It's that simple. You can throw some sort of "science" at me, but when it flies in the face of the past, not just the recent past, I just don't buy it."
And when you are presented with evidence that it DOESN'T 'fly in the face of the past', as for instance my comments in post #55, you simply ignore it.
Which is how you maintain your beliefs in the face of overwhelming proof to the contrary. Deny the evidence to the contrary and you are free to continue believing what you want to believe... truth be damned.
74. Daniel Bailey at 04:41 AM on 26 September, 2010Re: cruzn246 (72, et-way-too-many-al)
Nothing you've said at any point shows you have an understanding of science. At all. Or that you're anything less superficial than what you seem to be.
You ignore every scientific rebuttal of your, um, "opinions" (since they're obviously not based on science) and continue blithely on your rambling way.
Give us something solid to go on that shows we should ever take you seriously again. Or that you're here to learn something and not just here to waste everyone's time. Because as of now, we've no other conclusions to draw.
The Yooper
75. muoncounter at 04:55 AM on 26 September, 2010#72: "They will almost be in a free-fall. I would bet changes on the order of 2C in a century over the N hemisphere would happen easily."
-2C in a century is free-fall and the current global +0.13C per decade (that's 1.3C per century) -- and more for the NH isn't a warmup you can believe in?
76. cruzn246 at 05:11 AM on 26 September, 2010"There ARE cases where temperature peaked after CO2 did. For instance... now, various flood basalt incidents, the snowball Earth scenario ~650 million years ago, et cetera."
These temps are not in any kind of peak now. They are just warm for the last 500 years. If they keep rising nonstop the next couple hundred years maybe. The flood basalt incidents were in a completely different type of earth climate. Snowball earth, another different climate. Things were so different 500,000,000 years ago, including continental placement, that comparing to those times is like comparing to another world. Our whole atmosphere was different.
Let's try to keep this in the interglacial periods please.
77. cruzn246 at 05:29 AM on 26 September, 2010"-2C in a century is free-fall and the current global +0.13C per decade (that's 1.3C per century) -- and more for the NH isn't a warmup you can believe in? "
That's 1.3 per Century if it lasts a century. Don't confuse rate with actual amount. It's gone up about 1C in the last 100 years. That kind of change has happened before.
Of course I believe it's warming. I am alive. I was also alive in the 70s. Thank God it's mot like that anymore, although I think our break from that kind of weather is about to end.
78. cruzn246 at 05:38 AM on 26 September, 2010"There ARE cases where temperature peaked after CO2 did. For instance... now, various flood basalt incidents, the snowball Earth scenario ~650 million years ago, et cetera."
There was also a huge spike in water vapor being outgassed in those eras. That is why they called those hot periods back then warm and humid. It's not like CO2 was the only thing going way up.
79. cruzn246 at 05:49 AM on 26 September, 2010We just had a record summer for highest average low temperatures in my area. Guess why. Yep, we had the highest average dewpoints for the summer also. You know, that greenhouse gas no one mentions.
80. CBDunkerson at 05:50 AM on 26 September, 2010cruzn246, so your statement that CO2 rises never proceed temperature rises was... false, but we should ignore that and concentrate ONLY on a relatively recent period of glacial cycles during which there have been no sudden profound increases in CO2... except for the current human driven one. Which we should also ignore.
Yes, once we blinder ourselves to all evidence to the contrary your position only looks slightly ridiculous. Unfortunately you then go and ruin it with;
"There was also a huge spike in water vapor being outgassed in those eras. That is why they called those hot periods back then warm and humid. It's not like CO2 was the only thing going way up."
I'd explain why this is nonsense, but it obviously wouldn't make any difference. Enjoy your fantasy world where long term increased atmospheric water vapor is both the cause AND effect of temperature increases.
81. cruzn246 at 06:09 AM on 26 September, 2010"I'd explain why this is nonsense, but it obviously wouldn't make any difference. Enjoy your fantasy world where long term increased atmospheric water vapor is both the cause AND effect of temperature increases."
Well debunkerson, tell me what the total world concentration of water vapor is today. Oh, you don't know? No, nobody can answer that question, but you all think we know exactly how this whole atmosphere works. How the heck can we know when we can't put a reliable figure on such a crucial component? You can't.
Moderator Response: Further discussion of water vapor needs to be on the thread Water vapor is the most powerful greenhouse gas.
82. archiesteel at 06:13 AM on 26 September, 2010@cruzn246: "Well cripes man, it's amazing you have any doubters here with the way some of you treat someone who says no."
You don't just come here to say no, you come here repeat debunk denier arguments and refuse to respond to actual counter-arguments with scientific evidence.
What's more, you use a very aggressive tone and denigrate the fine scientists who have produced a mountain of research supporting AGW.
You are not interested in learning the truth, but only want to be comforted in your non-scientific opinion.
"We just had a record summer for highest average low temperatures in my area."
What's a "high average low temperature"?
I guess you're trying to say you've had "record low temperatures" in your area, is that it? Well, the fact it was cold in your area doesn't mean anything, especially when you agree that we are warming.
"You know, that greenhouse gas no one mentions"
If you're talking about Water Vapor, it is mentioned all the time. In fact, it was mentioned quite a few times in this thread alone, proving your wrong.
You seem to have a problem formulating a logically sound argument. Perhaps you should learn a bit more about the science before trying to argue with people who understanding better than you do?
@cruzn246: "Well debunkerson, tell me what the total world concentration of water vapor is today. Oh, you don't know? No, nobody can answer that question"
Actually, water vapor represents about 0.4% of the atmosphere.
Again, don't gauge what science knows based on your own ignorance.
Moderator Response: Further discussion of water vapor needs to be on the thread Water vapor is the most powerful greenhouse gas.
84. Daniel Bailey at 06:25 AM on 26 September, 2010Re: cruzn246 (84)
Magic 8-ball says 12,900 cubic kilometers in the air; or a bit more than the volume of Lake Superior (12,000 cubic kilometers).
For extra credit, the 4% increase in atmospheric water vapor since 1970 due to the higher temperatures is about equal to the volume of Lake Erie.
In case you had an enquiring mind.
The (Il mio nome è Nessuno) Yooper
Moderator Response: Further discussion of water vapor needs to be on the thread Water vapor is the most powerful greenhouse gas.
85. muoncounter at 06:26 AM on 26 September, 2010#77:"Of course I believe it's warming. ... I think our break from that kind of weather is about to end."
So you do believe in warming, but you also believe its all natural? Happened before, will happen again, nbd. At the risk of repeating an oft-seen graphic:
Let's see if we can spot the difference between today and previous episodes.
Hint: CO2 is the middle graph, note vertical scale on the right. Left-most point on that graph (the most recent) just peaks over 280ppm, which looks like the prior warm episodes.
Answer: Now we're at 390ppm, which would put the green line off the top of the chart. That didn't happen before on this time scale (you asked for glacial/interglacials only).
Still believe its all happened before? And exactly when is this ice age of yours going to happen?
86. cruzn246 at 08:25 AM on 26 September, 2010"Answer: Now we're at 390ppm, which would put the green line off the top of the chart. That didn't happen before on this time scale (you asked for glacial/interglacials only).
Still believe its all happened before? And exactly when is this ice age of yours going to happen?"
Great, we are at the highest CO2 rates in the last 450.000 years. Not even close to the highest temperatures. So what am I supposed to think?
I know one thing about the end of the last interglacial. Sea levels were a heck of a lot higher than they are now. There was also a lot less ice. That is why we are still in a warm period and not cooling off yet.
87. archiesteel at 08:54 AM on 26 September, 2010@cruzn246: temperatures are at the high end of the last 450,000 years, as well, though it will take a couple of decades until we get the full effect of anthropogenic CO2.
So, the reality is that temperatures are at the highest and ice cover is at the lowest since the last glacial period, even though the climate optimum was a couple of thousand years ago.
In other words, you have *no* idea what you're talking about. I suggest you refrain from making any more fallacious comment and thus avoid embarrassing yourself any further.
88. cruzn246 at 08:56 AM on 26 September, 2010"Actually, water vapor represents about 0.4% of the atmosphere."
Actually this is wrong. It ranges from 1 to 4% with the average being between 2 and 3%, but no one is really sure what that average is on any given day. According to NASA, they say the increase in water vapor is probably playing a bigger part in warming now than CO2, but they will not put numbers on either as far as the amount each is contributing.
Water Vapor Confirmed as Major Player in Climate Change
"The difference in an atmosphere with a strong water vapor feedback and one with a weak feedback is enormous," Dessler said.
They are just starting to get a handle on water vapor feedback. My prediction is that in ten years they will see it as an even more important player in warming. I think all you need is a
simple climate shift that has nothing to do with CO2 to put more water vapor in the air. You melt more ice, that means more water, that means less reflection , albedo, and you have a warmer more humid earth without adding any CO2. Does CO2 add to this? Sure, but I really think it's piece is grossly overestimated.
89. archiesteel at 08:59 AM on 26 September, 2010I'm responding to your erroneous Water Vapour claims on the correct thread.
90. cruzn246 at 09:25 AM on 26 September, 2010"@cruzn246: temperatures are at the high end of the last 450,000 years, as well, though it will take a couple of decades until we get the full effect of anthropogenic CO2.
So, the reality is that temperatures are at the highest and ice cover is at the lowest since the last glacial period, even though the climate optimum was a couple of thousand years ago.
In other words, you have *no* idea what you're talking about. I suggest you refrain from making any more fallacious comment and thus avoid embarrassing yourself any further."
They are at the high end? They are near a middle value for the period of the Holocene. They have been nearly 2C warmer than this in the Holocene. Temperatures during the Holocene have been above this level numerous times and dropped back again. The temperature has been bouncing around in a roughly 4C range for the last 10,000 years. The previous 4 interglacial periods all ended with temps at least 2C warmer than we are now.
Ice volumes are not as low as they were prior to the last glaciation.
Funny how it takes so long to get feedback from CO2. with water vapor the feedback is nearly immediate.
Sure you can say high end but they are not at their warmest by any means.
91. archiesteel at 09:51 AM on 26 September, 2010@cruzn246: I don't know why I'm wasting my time debating with a fanatic, but here goes:
"They are at the high end? They are near a middle value for the period of the Holocene. They have been nearly 2C warmer than this in the Holocene."
Actually, no, they haven't. Temperature now are way above the holocene mean, and higher than any average temperatures since the last glaciation.
"Funny how it takes so long to get feedback from CO2. with water vapor the feedback is nearly immediate."
Please learn what "feedback" means.
92. muoncounter at 09:51 AM on 26 September, 2010#86: "we are at the highest CO2 rates in the last 50.000 years. Not even close to the highest temperatures. So what am I supposed to think?"
Think: Temperatures will go higher. See, not that hard.
"Sea levels were a heck of a lot higher than they are now. There was also a lot less ice. " References for that?
"That is why we are still in a warm period and not cooling off yet."??? We are still(?) in a warm period because sea levels were higher at the end of the last interglacial? Does that make any sense to anyone?
93. archiesteel at 10:00 AM on 26 September, 2010@muoncounter: "Does that make any sense to anyone?"
No, it doesn't, and it seems the further we go the more shrill cruzn246 is becoming. I think he's starting to realize he's really in over his head with his limited scientific knowledge. He's beginning to break down, making less and less sense as counter-arguments pile up against his house of cards.
The next logical step for would likely be to start making strawman aguments and ad hominem attacks.
94. cruzn246 at 10:29 AM on 26 September, 2010"Actually, no, they haven't. Temperature now are way above the holocene mean, and higher than any average temperatures since the last glaciation."
I'm almost from Missouri. show where you get this from.
95. cruzn246 at 12:43 PM on 26 September, 2010"That is why we are still in a warm period and not cooling off yet."??? We are still(?) in a warm period because sea levels were higher at the end of the last interglacial? Does that make any sense to anyone?
If you understood the connection to sea levels and ice ages you would get it.
96. Daniel Bailey at 13:13 PM on 26 September, 2010Re: cruzn246 (95)
"If you understood the connection to sea levels and ice ages you would get it."
Insofar as you have presented no evidence to support your opinion, and stand in direct juxtaposition to more than a century of scientific research, it can be safely concluded that it is YOU who do not get it.
Capiche?
The Yooper
97. cruzn246 at 13:43 PM on 26 September, 2010Re: cruzn246 (95)
"If you understood the connection to sea levels and ice ages you would get it."
"Insofar as you have presented no evidence to support your opinion, and stand in direct juxtaposition to more than a century of scientific research, it can be safely concluded that it is YOU who do not get it."
Oh cripes. It is a well known fact that sea levels were much higher at the end of the last interglacial and temperatures were higher also. The sea level connection to ice ages is simply this. If you bring sea levels up to the level that they reached at the end of the last
interglacial you could effectively shut down the Gulf Stream. That would be what you all call a tipping point. This is how high the water was in FL at the end of the last interglacial. the blue area is what was not under water.
Moderator Response: Try the What does past climate change tell us about global warming? thread, or The significance of past climate change, or Working out future sea level rise from the past.
98. Daniel Bailey at 13:50 PM on 26 September, 2010Re: cruzn246 (94)
"I'm almost from Missouri. show where you get this from."
1. Increasing the level of a greenhouse gas in a planet’s atmosphere, all else being equal, will raise that planet’s surface temperature.
2. CO2 is a greenhouse gas.
3. CO2 is rising.
4. Therefore (given 1-3 above) the Earth should be warming.
5. From multiple converging lines of evidence, we know the Earth is warming.
6. The warming is moving in close correlation with the carbon dioxide.
7. The new CO2 (as shown by its isotopic signature) is mainly from burning fossil fuels.
8. Therefore the global warming currently occurring is anthropogenic (caused by mankind).
How about a complete guide to modern day climate change?
Or an illustrated guide to the latest climate science?
How about every scientific body in the world endorsing the science of global warming/climate disruption (use the term of your choice), as summarized by the National Academy of Science in May of this year:
"A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems….
Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small.
Such conclusions and theories are then regarded as settled facts .
This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
Have you seen enough?
Re: cruzn246 (97)
And by presenting no mechanism to support your opinion, you amply demonstrate that you simply have no idea about what you are talking about.
You are merely "hypothesizing" (the supposition that this is similar to pulling small primates out of dark places is completely unrelated).
The Yooper
99. muoncounter at 14:22 PM on 26 September, 2010#95: "If you understood the connection to sea levels and ice ages"
Again, what is the significance of this remark? Ice ages cause sea level to drop. But this is not about ice ages; its about causes of climate change. In today's world.
BTW, your map in #97 appears to be one of the 125ka highstand. It's lovely, but no geologist on earth would put the land area in blue. Please cite your source. And check Quaternary sea-level history of the United States; it'll help you get the chronology correct.
100. cruzn246 at 14:49 PM on 26 September, 2010How about a quick synopsis of GHG, CO2 and AGW:
1. Increasing the level of a greenhouse gas in a planet’s atmosphere, all else being equal, will raise that planet’s surface temperature.
Yep.
2. CO2 is a greenhouse gas.
Yep
3. CO2 is rising.
Yep
4. Therefore (given 1-3 above) the Earth should be warming.
How much is a guess at best.
5. From multiple converging lines of evidence, we know the Earth is warming.
No doubt
6. The warming is moving in close correlation with the carbon dioxide.
Correlation does not mean causation. Science 101.
7. The new CO2 (as shown by its isotopic signature) is mainly from burning fossil fuels.
Check
8. Therefore the global warming currently occurring is anthropogenic (caused by mankind).
How much is still a guess. There is no good reason we should not be warming now. We are still interglacial and still recovering from a relative low point, the "Little Ice age", in an interglacial cycle. These are the warmest temperatures lately, but not the warmest of the Holocene. We got warmer than this during the last interglacial also.
muoncounter
I checked the Quaternary map. It is better than the one I had. It still works for a reshaped FL that could screw up the Gulf Stream and trigger rapid cooling. If not the gulf stream than I suspect some other ocean current gets rearranged. I think that this is the trigger for ice
The Big PictureOftentimes we get bogged down discussing one of the many pieces of evidence behind man-made global warming, and in the process we can't see the forest for the trees. It's important to every so often take a step back and see how all of those trees comprise the forest as a whole. Skeptical Science provides an invaluable resource for examining each individual piece of climate evidence, so let's make use of these individual pieces to see how they form the big picture.
The Earth is warming
We know the planet is warming from surface temperature stations and satellites measuring the temperature of the Earth's surface and lower atmosphere. We also have various tools which have measured the warming of the Earth's oceans. Satellites have measured anenergy imbalance at the top of the Earth's atmosphere. Glaciers, sea ice, and ice sheetsare all receding. Sea levels are rising. Spring is arriving sooner each year. There's simply no doubt - the planet is warming.
And yes, the warming is continuing. The 2000s were hotter than the 1990s, which were hotter than the 1980s, which were hotter than the 1970s. 2010 is on pace to be at least in the top 3 hottest calendar years on record. In fact, the 12-month running average global temperature broke the record 3 times in 2010, according to NASA GISS data. Sea levels are still rising, ice is still receding, spring is still coming earlier, there's still a planetary energy imbalance, etc. etc. Contrary to what some would like us to believe, the planet has not magically stopped warming.
Humans are causing this warming
There is overwhelming evidence that humans are the dominant cause of this warming, mainly due to our greenhouse gas emissions. Based on fundamental physics and math, we can quantify the amount of warming human activity is causing, and verify that we're responsible for essentially all of the global warming over the past 3 decades. In fact we expect human greenhouse gas emissions to cause more warming than we've thus far seen, due to the thermal inertia of the oceans (the time it takes to heat them). Human aerosol emissions are also offsetting a significant amount of the warming by causing global dimming.
There are numerous 'fingerprints' which we would expect to see from an increased greenhouse effect (i.e. more warming at night, at higher latitudes, upper atmosphere cooling) that we have indeed observed. Climate models have projected the ensuing global warming to a high level of
accuracy, verifying that we have a good understanding of the fundamental physics behind climate change.
Sometimes people ask "what would it take to falsify the man-made global warming theory?". Well, basically it would require that our fundamental understanding of physics be wrong, because that's what the theory is based on. This fundamental physics has been scrutinized through scientific experiments for decades to centuries.
The warming will continue
We also know that if we continue to emit large amounts of greenhouse gases, the planet will continue to warm. We know that the climate sensitivity to a doubling of atmospheric CO2 from the pre-industrial level of 280 parts per million by volume (ppmv) to 560 ppmv (we're currently at 390 ppmv) will cause 2–4.5°C of warming. And we're headed for 560 ppmv in the mid-to-late 21st century if we continue business-as-usual emissions.
The net result will be bad
There will be some positive results of this continued warming. For example, an open Northwest Passage, enhanced growth for some plants and improved agriculture at high latitudes (though this will require use of more fertilizers), etc. However, the negatives will almost certainly outweigh the positives, by a long shot. We're talking decreased biodiversity, water shortages, increasing heat waves (both in frequency and intensity), decreased crop yields due to these impacts, damage to infrastructure, displacement of millions of people, etc.
Arguments to the contrary are superficial
One thing I've found in reading skeptic criticisms of climate science is that they're consistently superficial. For example, the criticisms of James Hansen's 1988 global warming projections never go beyond "he was wrong", when in reality it's important to evaluate what caused the discrepancy between his projections and actual climate changes, and what we can learn from this. And those who argue that "it's the Sun" fail to comprehend that we understand the major mechanisms by which the Sun influences the global climate, and that they cannot explain the current global warming trend. And those who argue "it's just a natural cycle" can never seem to identify exactly which natural cycle can explain the current warming, nor can they explain how our understanding of the fundamental climate physics is wrong.
There are legitimate unresolved questions
Much ado is made out of the expression "the science is settled." My personal opinion is that the science is settled in terms of knowing that the planet is warming dangerously rapidly, and that humans are the dominant cause.
There are certainly unresolved issues. There's a big difference between a 2°C and a 4.5°C warming for a doubling of atmospheric CO2, and it's an important question to resolve, because we need to know how fast the planet will warm in order to know how fast we need to reduce our greenhouse gas emissions. There are significant uncertainties in some feedbacks which play into this question. For example, will clouds act as a net positive feedback (by trapping more heat, causing more warming) or negative feedback (by reflecting more sunlight, causing a cooling effect) as the planet continues to warm?
These are the sorts of questions we should be debating, and the issues that most climate scientists are investigating. Unfortunately there is a large segment of the population which is determined to continue arguing the resolved questions for which the science has already been settled. And when climate scientists are forced to respond to the constant propagation of misinformation on these settled issues, it just detracts from our investigation of the legitimate, unresolved, important questions.
The big picture is that we know the planet is warming, humans are causing it, there is a substantial risk to continuing on our current path, but we don't know exactly how large the risk is. However, uncertainty regarding the magnitude of the risk is not an excuse to ignore it. We also know that if we continue on a business-as-usual path, the risk of catastrophic consequences is very high. In fact, the larger the uncertainty, the greater the potential for the exceptionally high risk scenario to become reality. We need to continue to decrease the uncertainty, but it's also critical to acknowledge what we know and what questions have been resolved, and that taking no action is not an option.
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Comments 101 to 104 out of 104:
101. cruzn246 at 14:57 PM on 26 September, 2010"A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems….
Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small.
Such conclusions and theories are then regarded as settled facts.
This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
I like how they covered their you know what here.
"This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
Very likely, but they are not certain. No doubt.
102. Tom Dayton at 15:01 PM on 26 September, 2010cruzn246, you are incorrect in stating that "correlation does not mean causation." Correlation is necessary but not sufficient as evidence of causation.
There are empirically-backed theoretical reasons for our prediction that CO2 levels will correlate with temperature. Those predictions were made long before it was even possible to adequately measure the global levels of either of those variables for sufficiently long to confidently detect that correlation. The correlation later was discovered to exist, thereby supporting the other empirical evidence and theory
103. johnd at 18:04 PM on 26 September, 2010Daniel Bailey at 13:50 PM, your quick synopsis was a little bit too quick.
Before you can use points 1-3 to arrive at 4, you have to decide one more condition as proffered in point 1, that being "all else being equal"
Where is the evidence that all else is indeed equal? Or has ever been equal for that matter.
104. RSVP at 18:05 PM on 26 September, 2010Daniel Bailey #56"So, essentially a global average temp of -2 degrees F, or about -18 degrees C. Thus, no liquid water anywhere and no life. All very well understood for over a hundred years."
...and since life did appear, one must assume there has always been some CO2. Not too much (mind you) lest it get too hot to support life. No, just the right amount to where life can get its start, and then reach the current equilibrium...
...the point at which creationist models almost begin to seem more attractive.
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Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us"The heat will come back to haunt us sooner or later..." --Kevin Trenberth, referring to our inability over the past 5 years to locate half a watt per square meter per year of energy accumulated on Earth as a result of anthropogenic warming of the planet, approximately half of the expected warming signal.
It's a sad fact that while Earth's oceans are expected to absorb the vast majority of anthropogenically induced imbalance of the global energy budget, our physical observations of the caloric state of the deep ocean are conspicuously sparse when compared to daily remote sensing revisitations enjoyed by research subjects amenable to orbital remote sensing platforms. In some ways our instrumentation of such far-flung places as Mars and Venus is better than what we deploy here on Earth in the abyssal depths. While we have solid theoretical grounding for predicting storage of excess heat in the ocean, without the means to directly measure and accurately quantify this effect we're left missing not only heat but also a useful means of testing and validating predictions of climate sensitivity to forcing.
As our technical capacities have risen to the challenge of dealing with an environment arguably more hostile to instrumentation than near-Earth orbital space, oceanographers at last are enjoying some of the same physical and scientific advantages as those long enjoyed by scientists working with space-based remote sensing platforms. The semi-autonomous Argo array represents a huge leap forward in our understanding of the characteristics of the upper ocean. With respect to anthropogenic climate change, of late we've been treated to increasingly dense and accurate measurements of upper ocean heat content, greatly refining our ability gather this important data.
Unfortunately the present Argo implementation is depth-limited and we thus still have no automated systems in place for data retrieval from the slightly over one half of the ocean
inaccessible to robotic probes. For this majority of ocean volume we still must rely on hardy investigators "going down to the sea in ships, that do business in great waters." We landlubbers wondering about "missing heat" and suspecting it may be found in the ocean can only be patient as we wait for salt-crusted mariner scientists to return to shore and write up their results.
The main reason for lamentation of "Trenberth's Travesty" is the declining upward pace over the past 5 years of the portion of ocean heat content (OHC) we're readily able to measure. We know that sea level rise (SLR) is principally caused by both thermal expansion of the oceans and water mass contributed by continued melting of terrestrial ice. Terrestrial ice alone cannot account for the continuing sea level rise we see in the face of the slackened pace of upper ocean warming. Juxtaposing continuing sea level rise against OHC we don't observe, we're left with a substantial technical mystery, an inability to "close the budget" of SLR as well as an inability to specifically account for the final destination of heat we know is accumulating on the planet ( Willis 2008 ). Failing the unlikely emergence of some new mechanism able to cause SLR, we may say with reasonable confidence that continued SLR can at least partially be attributed to accumulating OHC we can't directly "see," but merely saying so is no substitute for direct measurements.
Now we may say some significant progress has been made in tracking down "missing heat." In Journal of Climate Sarah Purkey of the University of Washington and NOAA's Gregory Johnson report on an ambitious project to quantify heat being stored in the abyssal ocean ( Warming of Global Abyssal and Deep Southern Ocean Waters Between the 1990s and 2000s: Contributions to Global Heat and Sea Level Rise Budgets ). By revisiting abyssal stations included in the World Ocean Circulation Experiment (WOCE) conducted in the 1990s, about 20% of Trenberth's famous "missing heat" appears to have been tracked down, found to be slowly traveling north from the Southern Ocean.
While integrating these new measurements into the global heat budget does not entirely close our observational gap, by producing their results Purkey and Johnson have crisply demonstrated how vast amounts of heat may have been left out of the budget for the simple reason of previously being invisible. Their work is also a compelling case for improving our capability to routinely measure with less extraordinary effort the majority of ocean volume we're presently forced to ignore when accounting for accumulation of heat. Finally, it seems reasonable to conclude that these measurements bolster our confidence in SLR as a proxy for increasing OHC.
Purkey and Johnson's abstract:
We quantify abyssal global and deep Southern Ocean temperature trends between the 1990s and 2000s to assess the role of recent warming of these regions in global heat and sea level budgets. We compute warming rates with uncertainties along 28 full-depth, high-quality, hydrographic sections that have been occupied two or more times between 1980 and 2010. We divide the global ocean into 32 basins defined by the topography and climatological ocean bottom temperatures and estimate temperature trends in the 24 sampled basins. The three southernmost basins show a strong statistically significant abyssal warming trend, with that warming signal weakening to the north in the central Pacific, western Atlantic, and eastern Indian Oceans. Eastern Atlantic and western Indian Ocean basins show statistically insignificant abyssal cooling trends. Excepting the Arctic Ocean and Nordic seas, the rate of abyssal (below 4000 m) global ocean heat content change in the 1990s and 2000s is equivalent to a heat flux of 0.027 (±0.009) W m–2 applied over the entire surface of the Earth. Deep (1000–4000 m) warming south of the Sub-Antarctic Front of the Antarctic Circumpolar Current adds 0.068 (±0.062) W m–2. The abyssal warming produces a 0.053 (±0.017) mm yr–1 increase in global average sea level and the deep warming south of the Sub-Antarctic Front adds another 0.093 (±0.081) mm yr–1. Thus warming in these regions, ventilated primarily by Antarctic Bottom Water, accounts for a statistically significant fraction of the present global energy and sea level budgets.
In an interview, coauthor Gregory Johnson expressed the amount of heat identified in this study in amusingly prosaic terms: the newly located reservoir of energy is akin to what would be
liberated by loading every man, woman and child on Earth with five 1,400 watt hairdryers each and running those appliances continuously for the 20 year interval between measurements.
Purkey and Johnson's results, mapped:
"Mean local heat fluxes through 4000 m implied by abyssal warming below 4000 m from the 1990s to the 2000s within each of the 24 sampled basins (black numbers and colorbar) with 95% confidence intervals and the local contribution to the heat flux through 1000 m south of the SAF (magenta line) implied by deep Southern Ocean warming from 1000–4000 m is also given (magenta number) with its 95% confidence interval." (Purkey and Johnson, 2010)
How can Antarctic Bottom Water (AABW) influence abyssal temperatures so far north of the Antarctic? To understand this, it's helpful to grasp the huge role in deep ocean circulation played by the Southern Ocean and the Antarctic. AABW is derived from enormous quantities of chilled, relatively saline and thus dense water sinking at the extreme south of the globe, in Antarctic waters. This mass of dense water is relatively free to travel north, first plunging off the Antarctic continental shelf and then hugging the bottom as it displaces warmer water. AABW is steered by bottom topography and Coriolis forces and only ceases moving and thus influencing abyssal temperatures when it has reached equilibrium density with surrounding water. Even after traveling some 60 degrees north of its source, density differences are still large enough to drive substantial amounts of AABW past the circulation barrier imposed by the equator, thus permitting diminished but still measurable circulation effects of AABW to be measured in the abyssal depths of the Northern Hemisphere.
A pair of illustrations of Antarctic and Southern Ocean circulation may be helpful in understanding the process of AABW transport.
"South (left) to north (right) section through the overturning circulation in the
Southern Ocean. South-flowing products of deep convection in the North Atlantic are converted into upper-layer mode and intermediate waters and deeper bottom waters and returned northward. Marked are the positions of the main fronts (PF – Polar Front; SAF – Sub-Antarctic Front; and STF – Subtropical Front), and water masses (AABW – Antarctic Bottom Water; LCDW and UCDW, Lower and Upper Circumpolar Deep Waters; NADW – North Atlantic Deep Water; AAIW – Antarctic Intermediate Water and SAMW – Sub- Antarctic Mode Water)" (Figure 1.9, SCAR "Antarctic Climate Change and the Environment" )
Role of Southern Ocean in global circulation ( Lumpkin and Speer, 2007 )
One might wonder, if AABW circulation is driven partly by the relative density of water chilled in the Antarctic, won't distribution of this water change as deep waters warm in response to heating by AABW circulation, thus robbing AABW of some of its physical transport impetus? This does seem to be the case; for instance, the interface between AABW and North Atlantic Deep Water (NADW) has deepened over the past few decades and as well there are indications of diminished abyssal circulation in regions of the North Pacific influenced by AABW, as would be expected in a scenario where density gradients are diminishing ( Johnson 2008, Kouketsu 2008 ). Numerous other variations in circulation behaviors controlled by thermally induced density variances may be found in Purkey and Johnson. Taken together, these indicators are broadly consistent with changes in the thermal regime of the deep ocean connected with AABW and its source.
It's important to note that to a greater or lesser extent the Southern Annular Mode (SAM) plays some role in controlling changes observed in Purkey and Johnson, not to the exclusion of secular changes outside of the SAM but significant nonetheless. Complications abound in forming an exact assessment of the proportionality of natural versus forced variations; the SAM itself appears to be in a process of adjusting to two anthropogenic influences, ozone depletion and greenhouse gas proliferation.
Beyond shedding enlightenment on a specific research topic, Purkey and Johnson's work suggests some improvements we could make in the level of urgency we attach to exploring our planet. NOAA is working on upgrading our ability to sample deep and abyssal ocean water via robotic instrumentation. As is so often the case, the pace of instrumentation improvements is set in part by budgetary limitations involving amounts of money small in the grand scheme of things. Purkey and Johnson show beyond doubt how vital better observational ability is when it comes understanding our role in shaping the climate; we're effectively blind to enormous changes in the physics of our planet because we won't make paltry expenditures for better "optics," a lamentable and unnecessary condition. Our instrumentational inability to closely track climate change is a general problem; it's truly odd that such a important research topic so crucial to public policy should find itself lacking the equipment to quantify changes nearly everybody agrees present us with multi-trillion dollar risk and decision choices and outcomes.
In terms of effective inaccessibility and remoteness, Earth's oceanic abyssal depths have aptly been compared unfavorably to extraterrestrial space.
For researchers investigating Earth's climate, orbital space is in some ways a far friendlier environment than the oceans. Instruments aboard satellites allow researchers to collect their data while lounging in shirtsleeve comfort, facing nothing more dangerous in the daily routine than slipping and falling while taking a morning shower.
Oceanographers often must wrest their primary information from the ocean, at personal risk, conducting their observations from the pitching, rolling decks of ships with course and speed set for instrument deployment as opposed to comfort and safety, directly exposed to the uncaring vagaries of fickle weather and heavy machinery. Errors in procedure, equipment or vessel failures or even inclement weather may exact the ultimate penalty on oceanographers seeing to the meticulous collection of data, career hazards not faced by many other scientists investigating climate-relate phenomena.
Quite apart from the kinetic drama of working from small ships on the surface of such storied locales as the notoriously stormy Southern Ocean, the sea is also extraordinarily costly in terms of the personal investment of time required to wrest every few hundred kilobytes of data from the cold dark of the bottom. After dealing with a commute of thousands of miles to their laboratory enviroment, scientists are rewarded with brief spurts of information separated by long intervals of plodding, akin to "crossing the ocean at a jogging pace" as NOAA's Gregory Johnson expresses the matter.
For all these reasons, it's worth pausing a moment in appreciation of the fanatical dedication and perseverance needed to collect data of the kind used to produce Purkey and Johnson's paper. The graphs and maps casually flung out in little essays such as the one above inadequately express countless thousands of cold and dripping hours spent in hostile conditions far from hearth and home. True enough it's an all-volunteer army, but recognition of this effort is still due
Posted by doug_bostrom at 04:40 AM
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Comments
Comments 1 to 34:
1. jyyh at 11:35 AM on 23 September, 2010Bering strait flow is probably too small to include in that wonderful image but I think it should be a two-headed arrow.
2. SoundOff at 13:09 PM on 23 September, 2010I wonder, with the ice packs breaking up in the north, if the now more open passages might be allowing new colder currents to flow south within the upper levels of the oceans. Think of cold fresh melt water spreading over the surface while the original warmer saline water is pushed down deeper. This might explain why we see less warming in the upper oceans than we expect. Just thinking out loud.
3. dana1981 at 13:41 PM on 23 September, 2010Nice job, doug. Very interesting stuff.
Excellent job Doug. Thanks for this. Have to "digest" the content before commenting on the science.
5. nigelj at 14:32 PM on 23 September, 2010There are several cooling / flat periods over the last 100 years of ocean temperatures, so surely this is an ocean cycle or sunspot affect or la nina, and surely its been identified?
6. scaddenp at 14:44 PM on 23 September, 2010The relevance of this paper is to total ocean heat content (OHC). Plenty of cycles to move heat around within the ocean without changing total OHC. (I'm not lost on calling it heat either). We barely have adequate measure of OHC now let alone anything remotely useful covering the last 100 year. If we did however, I would expect to periods of static and cooling because changes in solar and aerosols should have affected it. Climate is not single factor.
7. MattJ at 16:03 PM on 23 September, 2010I love the title! Unfortunately, the article is both long and dense, so I didn't finish it -- and am wondering how many in the target audience will finish it.
8. citizenschallenge at 16:36 PM on 23 September, 2010Yes, excellent, informative post. First class.
I'm back to wondering about how the Pacific Decadal Oscillation might interact with deep sea thermohaline circulation... mixing dynamics?
Any info?
9. citizenschallenge at 16:40 PM on 23 September, 2010MattJ #7 said:"I love the title! Unfortunately, the article is both long and dense, so I didn't finish it -- and am wondering how many in the target audience will finish it. "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
That is why ScepticalScience folks are writing the basic version explanations as well.
Also, don't forget - sometimes, one just needs the words to explain the situation.
10. adelady at 16:49 PM on 23 September, 2010Articles like this one, Matt, are like some books on our shelves. Even if we have read the whole thing, it's always instructive to return and reread with more understanding.
It's terrific, Doug. And we should all echo your sentiments about the fanatical dedication of people prepared to take such risks for the benefit of science. Gratitude to all of them.
11. Riccardo at 17:54 PM on 23 September, 2010I happened to work for a few days on a oceanographic ship in the much warmer and calm mediterranean waters. We had a simple task, take an instrument left at the bottom (2000 m) back home. The operation plan was simple, distributed to all of us printed on paper it was about a single page. The weather was fine and the sea smooth, i thought it was going to be almost a couple of days out at sea on vacation. It turned out to be the hardest 36 hours of continuos work of my life.When the instrument was finally on board, we were so tired that no one could eat or take a shower. Still wearing our wet clothes we hung over the deck for a long while drinking coffee. I commented that everything went wrong but my collegues laughed at me and said
"welcome to oceanography!"Thank you Doug for reminding me this experience.
12. dorlomin at 21:22 PM on 23 September, 2010Excellent article. A real addition to the blog. Sea level rise is like the shadow cast by the heat, finding a reasonable portion of that missing heat is a real big break.
13. doug_bostrom at 22:20 PM on 23 September, 2010Riccardo, ~36 hours happens to be the longest I've ever worked in a single shift, too! In my case (ironically!) standing in the middle of an old landfill outside of Houston, Texas, servicing instrument packages being sent down a prospective oil well. Stinky, muddy, hot, w/mosquitoes. Driller did not want to believe hydrocarbon show at the "wrong" place in the hole. An early lesson for me on how seriously stupid it is to burn petroleum after working so hard to get it. "Crude," so to speak.
Regarding parts of this heat distribution being cyclic, as I mentioned in the post it's probably the case that some of what's being measured is a natural feature, as natural as anything can be at this developing stage of the disruption game. It's even remotely possible that by some chance the -entire- apparent signal is down to some cyclic behavior. We don't know for sure; more measurements will help to resolve the proportionality of influences.
To get the full picture here, I highly recommend reading Purkey & Johnson's paper itself; my post is an absurdly compressed synopsis of the publication and is as much as anything a general remark on how ill-equipped we are to scrutinize what lies shortly past the end of our collective noses. P&J's paper on the other hand is a model of circumspection and caution. It's an education all by itself on the general topic of Southern Ocean circulation as well as providing an excellent list of references for becoming better acquainted with the subject of the Southern Ocean's influence on the rest of the planet. Read it completely twice before leaping to conclusions, that's the best course to set.
For my own part, I see a monotonous refrain in comments to the effect of "it's natural." To believe that this finding reflects only a natural process means expanding and then continuing to bear the burden of an already terminally cumbersome and awkward caveat.
Choosing to interpret this enormous bulge of heat as being unrelated to AGW as usual requires that one simultaneously believe a myriad of -other- things are also coincidentally entirely in keeping with predictions arising from some fairly simple physical principles we've set in motion. Long ago this chain of coincidences became conspicuous and has since reached the point of being far beyond the realm of probability worth the investment of our faith.
I'm not the sort to buy even a single lottery ticket so maybe I'm not the best judge of these things.
MattJ, it -is- long. I struggle with my bloviation; so much to say, so little of other people's time in which to say it.
14. Ken Lambert at 00:06 AM on 24 September, 2010doug_bostrom #Original post
"One might wonder, if AABW circulation is driven partly by the relative density of water chilled in the Antarctic, won't distribution of this water change as deep waters warm in response to heating by AABW circulation, thus robbing AABW of some of its physical
Chilled denser water slides down deep off Antarctica, travels north and warms the deep water up to the Equator. One would have thought it would have mixed and cooled such water.
The amounts of SLR and OHC increase from this mechanism seem to be small.
"Excepting the Arctic Ocean and Nordic seas, the rate of abyssal (below 4000 m) global ocean heat content change in the 1990s and 2000s is equivalent to a heat flux of 0.027 (±0.009) W m–2 applied over the entire surface of the Earth. Deep (1000–4000 m) warming south of the Sub-Antarctic Front of the Antarctic Circumpolar Current adds 0.068 (±0.062) W m–2. The abyssal warming produces a 0.053 (±0.017) mm yr–1 increase in global average sea level and the deep warming south of the Sub-Antarctic Front adds another 0.093 (±0.081) mm yr–1."
0.027 + 0.068 W/sq.m = 0.095 +/-0.071W/sq.m
Dr Trenberth's TOA imbalance is 0.9W/sq.m of which he can account for about 0.55W/sq.m with wide error bars.
Of the 0.35W/sq.m 'missing' the above analysis (0.095) accounts for about 27% - again with wide error bars.
A total contribution 0.146mm/yr of SLR is tiny compared with the current trend of 2.1 - 2.5mm/yr.
Oceanographers have a tough job - as a sailor myself I know what a heaving deck in a 50 knot storm is like.
Permanent tethered buoys reporting the oceans at regular coincident times is the ideal we should be financing - not technical fantasies like CCS.
15. doug_bostrom at 00:55 AM on 24 September, 2010Ken, yeah, and thanks for pointing that out, I did a poor (incomplete) job with explaining. It's a bit more complicated than what I suggested, there are several thing going on.
One problem is that I left out the "haline" part of "thermohaline circulation."
I'll fix the paragraph after pondering on it a bit.
I have to disagree w/you on the relative magnitude of the heat located in P&J 2010. 0.09 W/m2 is in itself a substantial fraction of Trenberth's gap and as well is an indicator of how "missing" does not automatically imply "does not exist." But I'm repeating myself.
16. doug_bostrom at 01:04 AM on 24 September, 2010I also ought to lighten up my dismal perspective on instrumentation by mentioning NOAA's plans to equip a subset of Argo buoys for deep operations as well as their scheme to deploy some lurking benthic samplers that will run on the bottom for an extended period of time before emerging to report back.
17. michael sweet at 01:20 AM on 24 September, 2010If the change in heat measured were due to natural cyclical processes you would expect that some areas would go down in heat content while others went up. This would be the case unless the process was very long. If it was long we would not see a large effect like what has been observed. Perhaps the few areas where heat content went down were due to a long term mechanism. The fact that most areas went up suggests a common mechanism--AGW.
Doug, excellent post as per your normal stuff. If people find two pages too long to read they can just read the introduction and the conclusion.
18. Badgersouth at 04:05 AM on 24 September, 2010Since the launching of the USS Nautilus in 1954, nuclear submarines have plied the depths of the world’s oceans. My working assumption is that these vessels collected a wealth of information about the temperature of the lower layers of the global ocean system.
I also acknowledge that the data collected by the fleets of nuclear submarines is highly classified.
Notwithstanding the classified nature of the data, wouldn’t it make sense for the IPCC to establish a special committee to discuss this matter with the governments of those countries with nuclear submarine fleets?
Perhaps there is way for the data to be made available without compromising national security concerns.
The stakes are high!. It’s worth a try.
19. KR at 04:19 AM on 24 September, 2010Doug Bostrom - Excellent article, it's extremely informative. I have to admit I was stunned to hear that part of the Antarctic Bottom Water (AABW) actually reaches the Northern Hemisphere.
Given the time frame of the Trenberth missing heat, are there indications ofchanges in circulation over the last decade that might be increasing transfer of heat to the bottom waters, away from what is currently measured by the ARGO program?
20. dorlomin at 04:30 AM on 24 September, 2010Badgersouth at 04:05 AM on 24 September, 2010Since the launching of the USS Nautilus in 1954, nuclear submarines have plied the depths of the world’s oceans= = = = = = = = = = = = = = = = = = = = = = = = = =The maximum operating depth of the Los Angeles class is usualy given at around 200m. Very very shallow operation compared to the depths of the ocean.
21. Badgersouth at 04:45 AM on 24 September, 2010@Dorlomin:
I didn't realize that the maximum operating depth of a nuclear submarine was that shallow.
Has the US Navy shared with climate scientists the temperature data that has been collected by nuclear submarines operating in the Arctic Ocean?
For obvious reasons, the Argos buoys have not been deployed there.
22. GFW at 06:07 AM on 24 September, 2010Yes, some Arctic data from the US Navy has been carefully released. If I recall correctly, Al Gore was involved in convincing them to do it.
Indeed military subs don't operate very deeply. They're optimized for their military missions, which only require that they can hide below the thermocline, not go super deep. However, one can assume that they can go deeper than the military publicly admits. The following link claims 300m max operating depth with likely hull collapse at 450m (again, somehow I suspect that hasn't been precisely tested with a billion+ dollar boat, so it's probably conservative, but it reinforces the point that another term for max operating depth is "never-exceed depth").http://www.fas.org/programs/ssp/man/uswpns/navy/submarines/ssn688_la.html
23. GFW at 06:10 AM on 24 September, 2010Apparently the Seawolf class can go deeperThe Ohio class is probably in-between.
24. Badgersouth at 06:40 AM on 24 September, 2010GFW:
I do recall that the US Navy released data about the thickness of the Arctic sea ice collected from nuclear subs, but I do not recall anything about ocean temperatures.
25. Rob Honeycutt at 07:02 AM on 24 September, 2010No one has mentioned this yet but I'm assuming this has implications for Dr Pielke's recent statement that "global warming has stopped" while referring to OHC.
26. Daniel Bailey at 07:32 AM on 24 September, 2010Re: Badgersouth, GFW
FBM's and attack subs are indeed designed for near-surface ops. Newer class subs will have a classified capability beyond that publicly revealed. "Research" vessels (not necessarily nuclear) exist with deeper dive capabilities.
Temperature, pressure and salinity data are all acquired during normal sounding operations (to get an accurate corrected depth) and should all have a time-stamp with a GPS accuracy-equivalent lat/long. I utilized a number of sounding datasets that I was able to pass San Board review & incorporate in various mapping products for the military (classified & unclassified) and the merchant marine (unclassified).
While there thus exists extensive datasets with good spatiotemporal resolution, security constraints will probably keep it from full utilization for OHC research purposes. A FOIA request from a connected Congressman or Senator, properly worded to degradate the true resolution and comprehensiveness of the datasets, could be used to obtain coverage to fill in any "gaps" in the Argo grid.
I'll close with this: every US sub commander is intimately acquainted with the story of the Thresher.
27. doug_bostrom at 13:16 PM on 24 September, 2010KR not to simply punt, rather because it's so complicated and I don't really know how to answer your question, probably the best way to start tracking down changes in circulation would be to dig into the P&J paper's references. In particular you might want to check Orsi's On the meridional extent and fronts of the Antarctic Circumpolar Current (full text, PDF) and follow citations of that paper forward in time.
28. Badgersouth at 06:58 AM on 26 September, 2010HELP!
In this posting and commnet thread, ocean heat content is expressed in W m–2.
In the posting and comment thread re Dr. Roger Pielke and the "missing heat", ocean heat content is expressed in Joules.
Why the use of two different measures?
What's the crosswalk between "W m-2" and "Joules."
29. Daniel Bailey at 07:32 AM on 26 September, 2010Re: Badgersouth (28)
My understanding is that Joules is a measure of power per unit time, while W m-2 is used to describe units of solar irradiance (the energy falling on a unitarea over a unit time). Not quite the same thing.
Try here.
Looks like it might be what you want.
But then, maybe nobody knows...
The Yooper
30. muoncounter at 07:53 AM on 26 September, 2010Yooper,
Joules is a measure of energy in the SI system.
Watts are Joules per second, the measure of power consumption (think 100 watt light bulb).
Watt/m^2 is a measure of energy per unit time spread out over an area. In this context, that is often called flux.
Thus 100 Watts/m^2 represents the power consumption of a 100 watt bulb spread out on a surface area of one square meter.
31. Badgersouth at 08:58 AM on 26 September, 2010@ Daniel Bailey & muoncounter:
Thanks for chiming in. I knew the basics.
I still do not understand why this article uses Watts/m-2 and the Pielke article uses Joules.
Perhaps I am missing something, but it seems to me that any measure of the heat content of the ocean must be done by volume. Watts/m-2 seems related to area only.
32. Badgersouth at 09:06 AM on 26 September, 2010@Daniel Bailey & muoncounter:
n. (Abbr. J or j)
1.The International System unit of electrical, mechanical, and thermal energy.
2.a.A unit of electrical energy equal to the work done when a current of one ampere is passed through a resistance of one ohm for one second.
2.b.A unit of energy equal to the work done when a force of one newton acts through a distance of one meter.
[After James Prescott JOULE.]
Per Answer.com
33. KR at 15:21 PM on 26 September, 2010Badgersouth - One Watt is one Joule per second.
This means that W/m^2 is the rate that energy arrives on a per-square-meter basis, while summing up all of those Joules over many seconds results in an energy sum that is the accumulated energy.
Think of this as in water: as gallons per minute versus total gallons in your swimming pool.
34. Badgersouth at 15:43 PM on 26 September, 2010KR:
Climate Change: The 40 Year Delay Between Cause and EffectGuest post by Alan Marshall from climatechangeanswers.org
Following the failure to reach a strong agreement at the Copenhagen conference, climate skeptics have had a good run in the Australian media, continuing their campaigns of disinformation. In such an atmosphere it is vital that we articulate the basic science of climate change, the principles of physics and chemistry which the skeptics ignore.
The purpose of this article is to clearly explain, in everyday language, the two key principles which together determine the rate at which temperatures rise. The first principle is the greenhouse effect of carbon dioxide and other gases. The second principle is the thermal inertia of the oceans, sometimes referred to as climate lag. Few people have any feel for the numbers involved with the latter, so I will deal with it in more depth.
The Greenhouse Effect
The greenhouse effect takes its name from the glass greenhouse, which farmers have used for centuries, trapping heat to grow tomatoes and other plants that could not otherwise be grown in the colder regions of the world. Like glass greenhouses, greenhouse gases allow sunlight to pass through unhindered, but trap heat radiation on its way out. The molecular structure of CO2 is such that it is “tuned” to the wavelengths of infrared (heat) radiation emitted by the Earth’s surface back into space, in particular to the 15 micrometer band. The molecules resonate, their vibrations absorbing the energy of the infra-red radiation. It is vibrating molecules that give us the sensation of heat, and it is by this mechanism that heat energy is trapped by the atmosphere and re-radiated to the surface. The extent to which temperatures will rise due to a given change in the concentration of greenhouse gases is known as the “climate sensitivity,” and you may find it useful to search for this term when doing your own research.
Most principles of physics are beyond question because both cause and effect are well understood. A relationship between cause and effect is proved by repeatable experiments. This is the essence of the scientific method, and the source of knowledge on which we have built our technological civilization. We do not question Newton’s laws of motion because we can demonstrate them in the laboratory. We no longer question that light and infrared radiation are electromagnetic waves because we can measure their wavelengths and other properties in the laboratory. Likewise, there should be no dissent that CO2 absorbs infrared radiation, because that too has been demonstrated in the laboratory. In fact, it was first measured 150 years ago by John Tyndall [i] using a spectrophotometer. In line with the scientific method, his results have been confirmed and more precisely quantified by Herzberg in 1953, Burch in 1962 and 1970, and others since then.
Given that the radiative properties of CO2 have been proven in the laboratory, you would expect them to be same in the atmosphere, given that they are dependent on CO2’s unchanging molecular structure. You would think that the onus would be on the climate skeptics to demonstrate that CO2 behaves differently in the atmosphere than it does in the laboratory. Of course they have not done so. In fact, since 1970 satellites have measured infrared spectra emitted by the Earth and confirmed not only that CO2 traps heat, but that it has trapped more heat as concentrations of CO2 have risen.
The above graph clearly shows that at the major wavelength for absorption by CO2, and also at wavelength for absorption by methane, that less infrared was escaping in to space in 1996 compared to 1970.
After 150 years of scientific investigation, the impact of CO2 on the climate is well understood. Anyone who tells you different is selling snakeoil.
The Thermal Inertia of the Oceans
If we accept that greenhouse gases are warming the planet, the next concept that needs to be grasped is that it takes time, and we have not yet seen the full rise in temperature that will occur as a result of the CO2 we have already emitted. The Earth’s average surface temperature has already risen by 0.8 degrees C since 1900. The concentration of CO2 in the atmosphere is increasing at the rate of 2 ppm per year. Scientists tell us that even if CO2 was stabilized at its current level of 390 ppm, there is at least another 0.6 degrees “in the pipeline”. If findings from a recent study of Antarctic ice cores is confirmed, the last figure will prove to be conservative [ii]. The delayed response is known as climate lag.
The reason the planet takes several decades to respond to increased CO2 is the thermal inertia of the oceans. Consider a saucepan of water placed on a gas stove. Although the flame has a temperature measured in hundreds of degrees C, the water takes a few minutes to reach boiling point. This simple analogy explains climate lag. The mass of the oceans is around 500 times that of the atmosphere. The time that it takes to warm up is measured in decades. Because of the difficulty in quantifying the rate at which the warm upper layers of the ocean mix with the cooler deeper waters, there is significant variation in estimates of climate lag. A paper by James Hansen and others [iii] estimates the time required for 60% of global warming to take place in response to increased emissions to be in the range of 25 to 50 years. The mid-point of this is 37.5 which I have rounded to 40 years.
In recent times, climate skeptics have been peddling a lot of nonsense about average temperatures actually cooling over the last decade. There was a brief dip around the year 2000 following the extreme El Nino event of 1998, but with greenhouse emissions causing a planetary energy imbalance of 0.85 watts per square metre [iv], there is inevitably a continual rising trend in global temperatures. It should then be no surprise to anyone that the 12 month period June 2009 to May 2010 was the hottest on record [v].
The graph below from Australia’s CSIRO [vi] shows a clear rising trend in temperatures as well as a rising trend in sea-level.
Implications of the 40 Year Delay
The estimate of 40 years for climate lag, the time between the cause (increased greenhouse gas emissions) and the effect (increased temperatures), has profound negative consequences for humanity. However, if governments can find the will to act, there are positive consequences as well.
With 40 years between cause and effect, it means that average temperatures of the last decade are a result of what we were thoughtlessly putting into the air in the 1960’s. It also means that the true impact of our emissions over the last decade will not be felt until the 2040’s. This thought should send a chill down your spine!
Conservative elements in both politics and the media have been playing up uncertainties in some of the more difficult to model effects of climate change, while ignoring the solid scientific understanding of the cause. If past governments had troubled themselves to understand the cause, and acted in a timely way, climate change would have been contained with minimal disruption. By refusing to acknowledge the cause, and demanding to see the effects before action is taken, past governments have brought on the current crisis. By the time they see those effects, it will too late to deal with the cause.
The positive consequence of climate lag is the opportunity for remedial action before the ocean warms to its full extent. We need to not only work towards reducing our carbon emissions to near zero by 2050, but well before then to begin removing excess CO2 from the atmosphere on an industrial scale. Biochar is one promising technology that can have an impact here. Synthetic trees, with carbon capture and storage, is another. If an international agreement can be forged to provide a framework for not only limiting new emissions, but sequestering old emissions, then the full horror of the climate crisis may yet be averted.
Spreading the Word
The clock is ticking. All of us who understand clearly the science of climate change, and its implications for humanity, should do what we can to inform the public debate. I wrote the original version of this article in February 2010 to help inform the Parliament of Australia. The letter was sent to 40 MPs and senators, and has received positive feedback from both members of the
three largest parties. To find out more about this information campaign, and for extensive coverage of the science of climate change and its technological, economic and political solutions, please visit my web site at www.climatechangeanswers.org.
Referencesi Gulf Times, “A Last Chance to Avert Disaster”, available at www.gulf-times.com/site/topics/article.asp? cu_no=2&item_no=330396&version=1&template_id=46&parent_id=26
ii Institute of Science in Society, “350 ppm CO2 The Target”, www.i-sis.org.uk/350ppm_CO2_the_Target.php, p.4
iii Science AAAS, ”Earth’s Energy Imbalance: Confirmation and Implications”, available (after free registration) at www.scienceonline.org/cgi/reprint/1110252v1.pdf, p.1
iv NASA, “The Ocean Heat Trap”, available at www.ocean.com, p.3
v NASA GISS temperature record (see http://climateprogress.org/2010/06/03/nasa-giss-james-hansen-study-global-warming-record-hottest-year/)
vi CSIRO, “Sea Level Rise”, available at www.cmar.csiro.au/sealevel/sl_drives_longer.html
Posted by alan_marshall at 19:23 PM
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1. perseus at 19:40 PM on 22 September, 2010Could this same 40 year lag in increased tempeatures be used as an 'explanation' by a sceptic for the Solar influence which peaked way back in the last century?
Response: No, the way climate time lag works is when the planet is in energy imbalance (eg - more energy coming in than going out), the planet steadily accumulates heat and warms. As it warms, it radiates more heat out to space until eventually, the energy out equals the energy in and the planet is back in equilibrium. So the way climate time lag works is the planet gradually warms over decades and the energy imbalance gradually shrinks.
That's not what we've seen over the last half century. After solar activity peaked in the mid-20th century, the planet's energy imbalance - rather than shrink - has actually increased as CO2 levels have increased.
2. sleepership at 21:07 PM on 22 September, 2010Is this time lag an absolute? Co2 now at around 390ppmv will 'only Be felt' in temperatures around the year 2050 (with all the significant feedback's)Or does that 390ppmv today have any effect on us?
Hansen has said that ice will melt and soften up in the arctic at 375-400ppmv- which is what is happening-
Or does time lag mean the CO2 emitted today will be around 30 years from now?
3. thingadonta at 21:09 PM on 22 September, 2010re#1.Perseus.
Yes, there is no reason why the ~40 year ocean heat lag should only apply to greenhouse gases. It also applies to heat from the sun. Of course it isn't mentioned, for sake of 'brevity', or some such.
The 'energy imbalance' referred to by the moderator and claimed to be increasing since the mid 20th century, as I understand it,has been modelled, not measured. And yes, you guessed it, modelled using greenhouse gas models. You can get a feel for their reasoning from the very first sentences in the following abstracts.
1.Earth's Energy Imbalance: Confirmation and Implications James Hansen,1,2* Larissa Nazarenko,1,2 Reto Ruedy,3 Makiko Sato,1,2 Josh Willis,4 Anthony Del Genio,1,5 Dorothy Koch,1,2 Andrew Lacis,1,5 Ken Lo,3 Surabi Menon,6 Tica Novakov,6 Judith Perlwitz,1,2 Gary Russell,1 Gavin A. Schmidt,1,2 Nicholas Tausnev3
"Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 ± 0.15 watts per square meter more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years."
2."Using a climate model that incorporates anthropogenic greenhouse gas emissions, scientists have recently concluded that the Earth is absorbing more energy than it emits. The energy imbalance, when compared to temperature measurements, indicates a lag in atmospheric warming."
4. CBDunkerson at 21:48 PM on 22 September, 2010sleepership, the cause of the lag is explained in the article. Basically, just as when you put a pot of water on the stove it does not immediately begin releasing heat to the air above the water so also does the extra heat going into the oceans take time to make its way into the atmosphere.
That said, yes there is also an immediate effect... some of the additional heat goes directly into the atmosphere. However, the surface of the Earth is 70% water. When you add in that this water is always moving and the vast VOLUME of the oceans it is obvious that the vast majority of the warming goes first into the oceans.
thingadonta, 'for sake of brevity'? Gee, I'd think it wasn't mentioned because the high solar activity in question was ~80 years ago.
5. sleepership at 21:57 PM on 22 September, 2010Thanks number 4 CB
The time lag as you explained- the immediate effects also can be felt- theoretically- the warming we feel today be goes back to the late 70s or early 80s- 30-35 years ago when the CO2 level was 330-340ppm.
Hansen and McKibben have put a maximum level of 'safe' CO2 at 350- but even that may be to high- but for all practical purposes 350ppmv is the goal we can only hope to reach.
6. muoncounter at 22:46 PM on 22 September, 2010"With 40 years between cause and effect"
This is perplexing. I see the role of thermal inertia as a mechanism for delayed heating response, but I have to wonder about what happens in the other direction. As is well known, the '91 Pinatubo eruption produced both a short-term cooling and flattening in the rate of increase of atmospheric CO2 (see Robock 2003 and the MLO mean rate of change table.
Why no lag in this case? Would such a large volcanic event be too short-lived to even make a dent in the lag you discuss here?
7. grypo at 22:50 PM on 22 September, 2010There is a new paper out from NOAA on deep ocean temperature measurements and I’m wondering how significant its findings are. Warming of Global Abyssal and Deep Southern Ocean Waters Between the 1990s and 2000s: Contributions to Global Heat and Sea Level RiseBudgets
I can’t find any other work that covers the deep ocean over the globe. My questions are:1. Is there any other study that measures that deep over the globe?2. Understanding the caveats and assumptions, how much does this help in filling out Earth’s energy budget (Trenberth’s travesty)?
8. sleepership at 23:17 PM on 22 September, 2010CO2 @ 390ppm-
do we see immediate effects? Was the heat the planet experienced this summer from 1980 C02 or from recently?
If from 1980- when CO2 was just passing 350ppm- then we are in deep deep trouble when today's levels overcome the 'inertia' around the year 2040.
The ice melt in the arctic seems over the last few years seems at the level of CO2 of between 370-390ppm however.
It seems that by 2020- an ice free arctic ocean is certainly possible- and that would see the CO2 lag from 1990 around 360ppm- but I assumed that an free arctic in the summer would be the product of a co2 level of 390 +----
All interesting- the 'Inertia' of lag time in warming seems possible in feedback's and general warming- but as far as Ice melt- the arctic is responding to the levels we currently have.
9. CBDunkerson at 23:26 PM on 22 September, 2010grypo, well the study found statistically significant (greater than 97.5% confidence) warming of deep ocean basins (below 4000 m) in the Southern ocean all the way down to the sea floor. That should put to rest arguments that heat can't possibly be making its way into the deep oceans quickly enough to be responsible for discrepancies in the energy and SLR balance calculations.
However, the amount of data gathered for this study is not sufficient to develop a robust GLOBAL picture of deep ocean warming. They make a good case that deep ocean heat needs to be accounted for in the energy and SLR budgets, but can't show that these make up the current budget gaps. With the available data they estimate 0.027 W/m^2 and 0.1 mm/yr global impacts from the sampled deep basins.
10. Riccardo at 23:28 PM on 22 September, 2010muoncounter and sleepership,the meaning of lag is not that the response starts whith a delay, but that the full effect will be seen later. If we apply a constant forcing equivalent to that of Pinatubo eruption, for example, it will cool much more than what we've seen; it cooled a few tenth of a degree just because it was very short (in time) and because of the inertia (lag) of the climate system.
11. CBDunkerson at 23:45 PM on 22 September, 2010Following on Riccardo's comments and going back to the 'pot of water' analogy... Pinatubo was the equivalent of turning the stove off for several seconds. All that dust in the air had an immediate impact on temperatures, but within a couple of years it had all fallen back to the surface and was no longer a factor. Yes, less heat went into the oceans during those few years and thus there is also a 'long term' impact, but since the 'forcing' from the dust only lasted a short time the cumulative cooling effect was small. When you add CO2 to the atmosphere the level stays elevated and thus continues to build up greater heat which circulates around in the oceans for decades before making its way to the atmosphere.
12. Arkadiusz Semczyszak at 23:47 PM on 22 September, 2010Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.:“The observed increase in global mean surface temperature (GMST) over the industrial era is less than 40% of that expected from observed increases in long-lived greenhouse gases together with the best-estimate equilibrium climate sensitivity given by the 2007 Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).”“Current uncertainty in climate sensitivity is shown to preclude determining the amount of future fossil fuel CO2 emissions that would be compatible with any chosen maximum allowable increase in GMST; even the sign of SUCH ALLOWABLE FUTURE EMISSIONS IS UNCONSTRAINED.”
Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate, Frank et al. 2010, Nature :“But themagnitudeof theclimate sensitivityof theglobal carboncycle (termed c), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections.”.“The average correlation between individual temperature reconstructions and the mean CO2 record is 0.47 over the pre-industrial 1050–1800 period (all years are AD), increasing to 0.57 with a 50-year CO2 response lag—such timing is consistent with modelled CO2 response to a temperature step change.” “Yet, great scatter in c, from a few to more than
40 p.p.m.v. per uC, closely reflects the choice of the individual temperature and/or CO2 estimates used for analysis. Particularly relevant to constraining sensitivities of the Earth’s coupled climate system is the amplitude of hemispheric to global-scale ...”“Approximately 40% of the uncertainty related to projected warming of the twenty-first century stems from the unknown behaviour of the carbon cycle, which is an important component of the global climate system.” “Coupled carbon–climate models show a wide range in feedback strength, with 20–200 p.p.m.v. of temperature-driven CO2 by 2100 ...”“Our results ... ... suggest 80% less potential amplification of ongoing global warming.”.
Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean. Khatiwala et al. 2009.: “Although much progress has been made in recent years in understanding and quantifying this sink, considerable uncertainties remain as to the distribution of anthropogenic CO 2 in the ocean, its rate of uptake over the industrial era, and the relative roles of the ocean and terrestrial biosphere in anthropogenic CO 2 sequestration.”
Summarize: ... such allowable future emissions is unconstrained ..., ... large uncertainties in global warming projections ..., ... great scatter ..., ... 40% of the uncertainty ..., ... wide range ..., ... 80% less potential amplification ..., ... considerable uncertainties ...
... and I have to invest billions of dollars in synthetic trees ... ?
13. grypo at 00:24 AM on 23 September, 2010Thank you CB!
Arkadiusz Semczyszak"Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.:"This paper discusses some uncertainty as to whether Climate Sensitivity is at the low range or whether aerosols contribute more to cooling than previously thought. But to understand fully what this paper suggests, you need to read the conclusions:"Even if the earth’s climate sensitivity is at the low end of the IPCC estimated ‘‘likely’’ range, continued emission ofCO2 at the present rate would exhaust in just a few decades the shared global resource of the incremental amount of CO2 that can be added to the atmosphere without exceeding proposed maximum increases in GMST. If thesensitivity is greater, the allowable incremental emission decreases sharply , essentially to zero at the present best estimate of climate ensitivity, and is actually negative for greater values of this sensitivity.
"Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean."Uncertainties as to the distribution of CO2 sink in the ocean does not change what we know about the carbon cycle and what content is in the atmosphere. The passage before what you quoted in the abstract says:"The release of fossil fuel CO2 to the atmosphere by human activity has been implicated as the predominant cause of recent global climate change1. The ocean plays a crucial role in mitigating the effects of this perturbation to the climate system, sequestering 20 to 35 per cent of anthropogenic CO2 emissions2, 3, 4. Although much progress has been made in recent years in understanding and quantifying this sink"
"... and I have to invest billions of dollars in synthetic trees ... ?"Nothing you've posted here would lead anyone to not invest in mitigation and adaption.
What stood out most in the article was the line "The mass of the oceans is around 500 times that of the atmosphere." This is an extremely compelling point specifying that the total effect of atmospheric conditions on climate change has at best a 1/500 effect compared to the oceans. This does not even include the effect of the land mass as well (perhaps another 1/7 more land/ocena versus atmospheric effect). This is the key point that has mad me a true skeptic on the oeverall effect of CO2 causing global warming. All energy in the atmospaher has a 1/500 effect compared to the oceans, and C)2 has a 1/100 effect compared to all greenhouse gases. The number DO NOT add up.
15. Phila at 00:28 AM on 23 September, 2010#12 Arkadiusz Semczyszak
As usual, you're cherrypicking, and ignoring the authors' interpretation of their own work.
"The more carbon dioxide you put in, the more acidic the ocean becomes, reducing its ability to hold CO2" said the study's lead author, Samar Khatiwala, an oceanographer at Columbia University's Lamont-Doherty Earth Observatory. "Because of this chemical effect, over time, the ocean is expected to become a less efficient sink of manmade carbon. The surprise is that we may already be seeing evidence for this, perhaps compounded by the ocean's slow circulation in the face of accelerating emissions...."
Khatiwala says there are still large uncertainties, but in any case, natural mechanisms cannot be depended upon to mitigate increasing human-produced emissions. "What our ocean study and other recent land studies suggest is that we cannot count on these sinks operating in the future as they have in the past, and keep on subsidizing our ever-growing appetite for fossil fuels," he said.
16. Jeff T at 01:15 AM on 23 September, 2010Greenhouse gases do trap radiation, but greenhouses stay warm largely because they prevent convection. Thus, the statement, "Like glass greenhouses, greenhouse gases allow sunlight to pass through unhindered, but trap heat radiation on its way out." is incorrect and should be modified. Even in a basic version, statements should be accurate.
17. beam me up scotty at 01:41 AM on 23 September, 2010Question: What percentage of the current .8C warming is due to CO2 that was emitted in 1970? Can that be calculated?
18. Ned at 02:10 AM on 23 September, 2010nerndt writes: What stood out most in the article was the line "The mass of the oceans is around 500 times that of the atmosphere." [...] This is the key point that has mad me a true skeptic on the oeverall effect of CO2 causing global warming. All energy in the atmospaher has a 1/500 effect compared to the oceans, and C)2 has a 1/100 effect compared to all greenhouse gases. The number DO NOT add up.
First off, the statement "C02 has a 1/100 effect compared to all greenhouse gases" is just plain wrong. Because the effects of different GHGs overlap, it's not straightforward to say that gas X causes percentage P of the total effect, while gas Y causes percentage Q. But CO2 clearly has a large warming effect on the climate. See
How do we know more CO2 is causing warming?Water vapor is the most powerful greenhouse gas
As for your general idea that since the mass of the ocean is much greater than the mass of the atmosphere, we can safely ignore climate change ... well, that just makes no sense.
The mass of the ocean was just as large at the end of the previous interglacial, but that didn't prevent the very radical climate change in which ice sheets spread southward for 80,000 years, eventually covering the place where I now sit with over 2 km of ice. Why would the mere existence of massive oceans prevent us from altering the climate in a similarly dramatic fashion in the opposite direction?
That's just wishful thinking, frankly.
19. muoncounter at 02:24 AM on 23 September, 2010#10:"meaning of lag is not that the response starts with a delay, but that the full effect will be seen later."In addition to 'turning off the burner' for a bit, the flattened rate of increase in CO2 after Pinatubo also 'took the lid off the soup pot' (its lunch time here). This essentially delays the continued heating and that should have an effect on the furious discussion over Hansen's 1988 projections.
#11: "continues to build up greater heat which circulates around in the oceans for decades before making its way to the atmosphere. "
The deep oceans are very cold. I would imagine the lag for measurable ocean heating is orders of magnitude more than 40 years. Since the air heats up (and loses heat) far more rapidly, why does ocean heat storage even enter into the discussion of surface (air) temperatures?
20. archiesteel at 02:33 AM on 23 September, 2010Is it just me, or are contrarians becoming increasingly sloppy here?
I guess it's a tribute to the science presented here that there would be so many scientifically poor comments trying to attack the points made in the articles: the more influential a science web site becomes, the more it is perceived as a threat by those who are politically opposed to it. Thus, the greater the number of contrarian/trolling comments.
21. dana1981 at 04:39 AM on 23 September, 2010beam me up scotty @ #17 - see Quantifying the human contribution to global warming.
Short answer, it's approximately 100% over the past 35 years and approximately 80% over the past century.
22. CBDunkerson at 05:03 AM on 23 September, 2010BmuS #17, dana1981's answer is probably the most useful you'll get. If you are really looking for the warming from CO2 emitted in JUST the year 1970 then we are talking about less than 2 ppm and the resulting warming would be exceedingly tiny. If you meant all CO2 emitted up THROUGH 1970 that's a much bigger factor, but difficult to quantify. Let's say CO2 had stabilized at the 1970 level. I think that was around 320 ppm. In that case, assuming a climate sensitivity of 3 for a doubling of CO2, I get;
Since we are 40 years past 1970 pretty much all of that warming should have now been cycled through into the atmosphere. Obviously, different climate sensitivity factors would yield different results, but the current 0.8 C warming is consistent with the 3 C 'fast feedback' sensitivity estimate.
23. johnd at 06:05 AM on 23 September, 2010On the point made in the lead article of this topic of CO2 properties as having been established in the laboratory, the behavior in the atmosphere should follow.The absorption of IR, being thermal energy, heat, in the atmosphere falls within certain limits due, not to the properties of CO2, but must be due that of the environment itself as CO2 can absorb heat to temperatures far in excess of normal conditions without any change of state occurring as this chart shows.The ability of it to radiate heat off, transfer heat to other adjacent matter will depend again on the state of the environment rather than any specific property of CO2 given it remains a gas at normal pressures at temperatures well in excess of anything within the normal environment.
24. nerndt at 06:06 AM on 23 September, 2010As for your general idea that since the mass of the ocean is much greater than the mass of the atmosphere, we can safely ignore climate change ... well, that just makes no sense.
The mass of the ocean was just as large at the end of the previous interglacial, but that didn't prevent the very radical climate change in which ice sheets spread southward for 80,000 years, eventually covering the place where I now sit with over 2 km of ice. Why would the mere existence of massive oceans prevent us from altering the climate in a similarly dramatic fashion in the opposite direction?
Hi Ned. The point I was trying to make is that the largest contributor to any global warming is not the atmospher, but the water and land masses. The atmosphere only has 1/500 (or less) overall mass than the oceans and has minimal effect. The one time this may not be the case would be in a large catastrophic event (huge volcano or metror strike) which then changes the absorption of energy by the oceans and land masses and quickly causes climate change.
25. nerndt at 06:11 AM on 23 September, 2010repsonse to #18 Ned at 02:10 AM on 23 September, 2010
Ned - Of course global warming and cooling occurs, but CO2 has a minimal effect being a small percentage of greenhouse gas effect and that the atmosphere has a minimal effect on the overall energy of the earth (being more than 1/500 of the totla mass).
Can anyone here see the big picture? The key point is that mankinds increase of CO2 to the atmosphere pales in comparison to the effects on the oceans and land by other conditions. Atmoshperic conditions are trivial.
Moderator Response: See the post (and take the discussion there): CO2 effect is weak
26. CBDunkerson at 06:28 AM on 23 September, 2010nerndt #25: "Atmoshperic conditions are trivial."
This is simply false. Basic physics tells us that without the atmosphere the planet would be about 33 C colder... and thus a solid ball of ice.
The amount of heat retained in the atmosphere itself is SMALL (not "trivial") compared to the amount in the oceans, but the atmosphere is CAUSING a great deal of that oceanic heat accumulation.
27. muoncounter at 06:40 AM on 23 September, 2010#22:"If you meant all CO2 emitted up THROUGH 1970"A cumulative plot using the CDIAC data shows that most of the emissions prior to 1950 or so don't make much of a contribution compared to everything since. See the cumulative graph in the figures here, for example. The caption says "Half of 270 Gtons [the cum to 2000] emitted since 1974". So if we are just now seeing the heating effects of the first half (its ~40 years post 1974) and have yet to see the heating effects of the second half --- ouch!!!
For example, arctic ice melt started accelerating in the '80s; was that due to cum CO2 up to the 40's? That's why I'm still having trouble wrapping my head around a 40 year lag.
28. Riccardo at 06:44 AM on 23 September, 2010john,"The absorption of IR, being thermal energy, heat, in the atmosphere falls within certain limits due, not to the properties of CO2 [...]"
It's not so. First of all, IR is an electromagnetic wave as any other. It is emitted by warm bodies and this is why it is associated to heat. The absorption properties of a molecule depend on the characteristic frequencies of vibration of the molecule which in turn depend on the physical properties of the chemical bond. No relation with temperature here. The environemnt has an impact on the width of the absorption frequency (and very little on the central frequency) but not on it's ability to absorb or radiate EM waves (apart from
extreme "pathological" cases which are not relevant to our atmosphere). In short, your claims are physical absurdities.
29. johnd at 06:52 AM on 23 September, 2010CBDunkerson at 06:28 AM, is it not instead that the ocean, and land, heat accumulation that is causing the warmth in the atmosphere.Incoming solar radiation must first be intercepted and absorbed by matter on the surface BEFORE being converted to IR that then transfers into the atmosphere. How near surface temperatures just below the surface vary over the course of a year indicates that at times incoming solar energy is excess of what is being lost into the atmosphere and so is accumulated as thermal energy below the surface, whilst at other times incoming solar radiation is less than that being lost to the atmosphere from below the surface where the thermal energy stored begins to decline.
30. johnd at 07:33 AM on 23 September, 2010Riccardo at 06:44 AM, I think you are making the same point as I was. The properties of CO2 allow it to absorb and radiate thermal energy over a far greater range than what is found in the natural environment, and it is the environment itself that determines the width of the absorption frequency.
31. scaddenp at 08:04 AM on 23 September, 2010john, I remain extremely confused by both your posts. "far greater range than found in natural environment". What unnatural environment are you talking about then?
That temperature of surface varies with season is hardly surprising, nor is the globally, annually averaged heat capacity of surface materials varying in any significant way on the time scales we are interested in. I fail to see what you are driving at here.
32. Riccardo at 08:20 AM on 23 September, 2010johnd,I'm making the opposite point, molecular absorption of CO2 (or any other molecule, for that matter) is an intrinsic property of the molecule. Pressure and temperature of the gas only slightly widen and shift the absorption band. Try a google search for pressure and Doppler broadening.In accurate radiative transfer codes the broadening effects are taken into account because the "wings" of the wider emission at higher temperature and pressure near the ground is less absorbed in the upper atmosphere. But these are subtleties.
33. johnd at 08:22 AM on 23 September, 2010scaddenp at 08:04 AM, re "unnatural environment", obviously the laboratory Phil, the properties of CO2 as proven in the laboratory as referenced in the lead article, and illustrated in the diagram posted.
Re your second comment, think cause and effect.
34. johnd at 08:31 AM on 23 September, 2010Riccardo at 08:20 AM, that is exactly the point I am making. As the diagram indicates, at 1 bar pressure the absorption band for thermal energy exceeds the range of 200K to 400K, that limitation being solely the range of the diagram.
For comparison think H2O and the changes of states that occur that affect the absorption and release of thermal energy, and how they relate to the natural environment.
John, no significant change means no cause. Unlike GHG concentrations. As to whether laboratory measurements are born out in the natural world, then I can only point you at the classic Ramanathan and Coakley 1978 paper which tested just that, confirmed by numerous other studies since.
36. MichaelM at 08:55 AM on 23 September, 2010Johnd:
The chart at #23 is just a pressure-temperature phase diagram and has nothing to do with IR absorption bands. It indicates at what pressure/temp combination CO2 changes state eg at 10Bar/225K CO2 will be liquid and boil at 230K. The 200/400 limits of tempeature are just what the creator of the diagram chose.
It looks like the colored-in version of this.
37. Riccardo at 09:18 AM on 23 September, 2010johnd,in #28 I copied part of your previous post and said it was not true. Maybe now you agree with me.In #34 you're switching argument:"As the diagram indicates, at 1 bar pressure the absorption band for thermal energy exceeds the range of 200K to 400K, that limitation being solely the range of the diagram."As MichaelM already said, there's no relation between a PT diagram and vibrational absorption/emission. That diagram just tells you that at 1 bar pressure CO2 is a gas between 200 and 400 K. Good to know, but then what? There's no thermal energy nor absorption lines shown there.
38. johnd at 09:41 AM on 23 September, 2010Riccardo at 09:18 AM, can you perhaps clarify these points for me,1 - at what temperatures does CO2 exist as a gas?
2 - what is the range of temperatures that CO2 absorbs thermal energy and emits thermal energy?
39. scaddenp at 10:10 AM on 23 September, 2010John - answer to 1 and 2 would be "all temperatures and pressures found in the atmosphere. (pressures of 1bar or less). Again, the relevance of your questions to anything in climate is hard to guess.
40. johnd at 10:27 AM on 23 September, 2010scaddenp at 10:10 AM, it all comes back to trying to establish how as mentioned in the lead article CO2 "is “tuned” to the wavelengths of infrared (heat)" when it is clear that it absorbs and emits thermal energy at wavelengths beyond that "tuned" range found in the atmosphere.Can you elaborate on your answer as to clarify whether CO2 also absorbs and emits thermal energy at temperatures and pressures BEYOND those found in the atmosphere, and thus is not "tuned" to any specific range.
41. Phila at 10:45 AM on 23 September, 2010#25 nerndt
It's really too bad so many climatologists are in the dark on this point. I guess they're just dumb, huh?
42. scaddenp at 11:05 AM on 23 September, 2010John - massive confusion here. IR is not heat for starters. Heat is energy being transferred by conduction between bodies at different temperatures. IR is energy as electromagnetic radiation. A CO2 molecule DOES absorbs radiation only in certain frequencies. It is anything but "clear" that it does otherwise. However, the atmosphere is also warmed by conduction. A molecule excited by absorption "heats" other molecules by collision. The CO2 molecule will also gain energy by collision with other molecules. The temperature of the atmosphere reflects both processes.
43. scaddenp at 11:26 AM on 23 September, 2010Also, yes, the atmosphere emits radiation in approximately the spectrum of the Planck's Law for a blackbody radiator (modified by the gas absorption bands).
44. jyyh at 12:24 PM on 23 September, 2010I'd like to point out that carbon fibers do not really decompose in a short time. To use these in construction and such would be preferable to many other materials.
45. alan_marshall at 17:21 PM on 23 September, 2010Re:#8.sleepership
You have seen the future we are currently headed for, and it is very frightening indeed. The following extract from your comment on my article is insightful:
“Was the heat the planet experienced this summer from 1980 C02 or from recently? If from 1980- when CO2 was just passing 350ppm- then we are in deep deep trouble when today's levels overcome the 'inertia' around the year 2040”
A deep political problem at the moment is that the majority of our politicians see the current warming of 0.8 C (if they concede there is any connection to CO2 at all) as being related to the current atmospheric concentration. The equilibrium temperature rise for 390 ppm is in fact at least 1.4 C, so we are only part way there. The stated goal of the Copenhagen Accord of keeping global warming below 2 C is looking increasingly difficult to achieve.
The only ray of hope is that the oceans have not yet absorbed all of this heat. They will absorb it, and the surface temperature will rise as projected, if the current energy imbalance is not reduced. We need not only to move rapidly to a near-zero carbon economy – we need to remove the bulk of the CO2 emitted from 1750 up till now. That will require either carbon sequestration on an industrial scale, or geoengineering.
46. jyyh at 18:30 PM on 23 September, 2010Question: Did the economic recession in the 1930s contribute much to the mid 20th century cooling, as there is this delay?
47. Arkadiusz Semczyszak at 18:47 PM on 23 September, 2010“Nothing you've posted here would lead anyone to not invest in mitigation and adaption.”
The aim of the actions already adopted in Kyoto was that the cost of fighting the AGW, ONLY (and solely) suffered final consumers (therefore: "normal" people), so that the producers of energy - due to rising costs - not moved their production to countries where there is no this "struggle."
This is not true. Indeed, my aim was not to summarizing the work of the authors - which I cited. Everyone knows that of teams the authors - cited the work (especially the second and third) is an “avowed” great proponents of the theory of AGW. If, however, and they have such fundamental questions ... (And that was my goal - to submit questions - I hope not omitted any of their doubts - because only then - if I ignored this question - it would be "cherrypicking").
For example, does the concentration of CO2 in the atmosphere will increase - for whatever reason - an additional 20 or 200 ppmv in the XXI century must be the great importance - what specific actions we take. Being a huge difference - in the context of chaos theory - "the wings of a butterfly" - indeedfundamental.
These questions show that it really practically nothing (sufficiently accurately) do not know what will happen - for 40 years - from "our" CO2. Instead, there are serious reasons for that, not only in the Himalayan glaciers will melt by at least 300 years. In one word: "clock" - almost certainly - “not ticking "...
Such a large number of papers of supporters of the theory of AGW, containing such a large question - written in recent times, is probably the result of appeal (2008 - The IPCC Must Maintain Its Rigor) Susan Solomon (real boss section "of science," the IPCC):“The climate system continues to change and science continues to improve, so policy must be kept current with our best understanding. Reformulating the science/policy interface should be considered and be open to change but must acknowledge lessons from the past. ...” “... if a rigorous scientific basis is to continue to inform the growing challenge of decision-making on climate change.”In 2010, Solomon does not know (but) nothing concrete (sufficiently accurately) about-at least - 1 / 3 warming - Guardian: “She said it was not clear if the water vapour decrease after 2000 reflects a natural shift, or if it was a consequence of a warming world. If the latter is true, then more warmingcould see greater decreases in water vapour, acting as a negative feedback to apply the brakes on future temperature rise.” “It shows that we shouldn't over-interpret the results from a few years one way or another.”
Korhola: “Decision-makers should make sensible choices regarding theoverall benefits in the environment of UNCERTAINTY.”
Rather than pay for the synthetic tree CO2 removes, I will pay for research such as thermo-nuclear fusion, or efficient energy storage in solar and wind power (in the periods when they do not produce energy) - it is always useful(for example, here is an interesting use of the thermal inertia of the usual molten salt).
48. archiesteel at 01:53 AM on 24 September, 2010@Arkadiusz: first, you should really stick to simple sentence, as your English does not appear to be strong enough to form complex sentences without making them confusing (non-English speaker, here).
Second, you make a couple of puzzling statements:
"For example, does the concentration of CO2 in the atmosphere will increase - for whatever reason - an additional 20 or 200 ppmv in the XXI century must be the great importance - what specific actions we take. Being a huge difference - in the context of chaos theory - "the
Chaos theory and the Butterfly effect have little to do with long-term trends and the clear effects of additional CO2 in the atmosphere. You seem to be implying (I may be wrong, for that paragraph is unclear) that more CO2 simply means more uncertainty in the resulting effect. That is not true, and seems to be a misunderstanding of what Chaos Theory is about.
"These questions show that it really practically nothing (sufficiently accurately) do not know what will happen - for 40 years - from "our" CO2."
Quantify "sufficiently accurately", please. Just because we don't have exact predictions doesn't mean we can't say it will be warmer using a climate sensitivity value of about 3C.
"Instead, there are serious reasons for that, not only in the Himalayan glaciers will melt by at least 300 years. In one word: "clock" - almost certainly - “not ticking "."
I don't know what you're trying to say, here. As I said earlier, keep to short, factual sentences. Are you implying that there is no cause for alarm and therefore we shouldn't be worried because we have plenty of time to wait and see? That sounds terribly irresponsible.
"If the latter is true, then more warming could see greater decreases in water vapour"
I know this is quoted from an article, but it's important to note this isn't directly attributed to Solomon. In fact, it seems to be an extrapolation made by the journalist, and one that appears extremely unlikely. Warmer world = more water vapor over the long run.
"Rather than pay for the synthetic tree CO2 removes, I will pay for research such as thermo-nuclear fusion, or efficient energy storage in solar and wind power (in the periods when they do not produce energy) - it is always useful (for example, here is an interesting use of the thermal inertia of the usual molten salt)."
Okay, I first thought your mention of the synthetic tree was a image representing all CO2 mitigation efforts, but now you seem to say it is a real artefact? I'm confused.
Efficient energy storage for solar and wind (using molten salt, for example) *are* ways to mitigate CO2 emmissions by lowering our use of fossil fuels. As for nuclear fusion, I'm all for it, but it may still take decades to get something that requires less energy to control than it produces...however, there's nothing preventing us from pursuing that research *in addition* to mitigation efforts, right?
Again, sorry if I misunderstood some of your post.
49. Phila at 02:06 AM on 24 September, 2010#47 Arkadiusz Semczyszak
If, however, and they have such fundamental questions ...(And that was my goal - to submit questions - I hope not omitted any of their doubts - because only then - if I ignored this question - it would be "cherrypicking").
Of course it's cherrypicking. In addition to ignoring the authors' conclusions, you also ignored the fact that the "uncertainties" to which they refer at the beginning of their paper are precisely what their paper tries to address. That's why they say, "Here we address these questions [i.e., these uncertainties] by presenting an observationally based reconstruction of
the spatially resolved, time-dependent history of anthropogenic carbon in the ocean over the industrial era."
In other words, you're treating the paper's initial acknowledgment of existinguncertainty as the take-away message of their paper, which is an absurd way to approach the matter. Scientists are trained to communicate in a measured way, and there's nothing clever or rigorous about the "skeptical" stunt of using this basic convention of scientific discourse as a weapon against science itself.
The intellectual pathology that sees uncertainty about AGW as positive is a whole other matter. (Where uncertainty exists, things can also be worse than we expect.)
So yeah, that'd be cherrypicking, undertaken in defense of a position that's logically incoherent.
50. Badgersouth at 02:33 AM on 24 September, 2010Since the launching of the USS Nautilus in 1954, nuclear submarines have plied the depths of the world’s oceans. My working assumption is that these vessels collected a wealth of information about the temperature of the lower layers of the global ocean system.
I also acknowledge that the data collected by the fleets of nuclear submarines is highly classified.
Notwithstanding the classified nature of the data, wouldn’t it make sense for the IPCC to establish a special committee to discuss this matter with the governments of those countries with nuclear submarine fleets?
Perhaps there is way for the data to be made available without compromising national security concerns.
The stakes are high!. It’s worth a try.
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Does Climate Change Really Matter?Guest podcast by Kevin Judd (a transcript of a radio podcast)
Climate scientists are telling us that the earth's average temperature is going to rise 2 to 3 degrees over the next 50 to 100 years. But does it really matter that temperatures will rise this much?
You might think that this rise tempertures only means that winters will be a little milder and summers a little hotter, which does not sound like something to be bothered about. Unfortunately, it is not that simple. The effects you are most likely to experience is an increase in extreme weather. For example, an increase in extreme heat-waves in summer, and at other times an increased likelihood of heavy rain, hail, and high winds, that lead to flooding and wind damage. In higher latitudes heavier snow falls are expected too, which might seem contradictory, but it is not.
So why does global warming cause an increase in storms? Big storms and extreme weather require a lot of energy to drive them. You might know that a pot will simmer on the stove for long time, but turn up the heat just a little, and it soon boils over. The same happens for big storms on earth. The additional heat from global warming means that the weather will more often boil-over into very big storms.
We are already seeing this happen. Insurance companies, who keep careful records of damaging storms, have seen the frequency of big storms triple in the last 30 years. Big storms that used to occur only once every one hundred years are now ocurring about every 30 years. Similarly, heat-waves are more common and severe, which, of course, means more wild fires.
Scientists cannot attribute to climate change any one extreme weather event, like say the recent hail-storm in Perth, or the flooding in Pakistan, but the trend to increasingly extreme weather can be directly attributed to global warming.
Anyone who tells you that you and future generations are not going to be effected by the consequences of climate change, either does not understand how weather and climate works, or is being deliberately misleading.
In my next segment I will consider what we can all do to prevent the damaging effects of climate change.
NOTE: this post is also being "climatecast" by Kevin Judd on RTR-FM 92.1 around 11.30 AM WAST today. You can listen to a streaming broadcast of RTR-FM online viahttp://www.rtrfm.com.au/listen. Please keep in mind that these podcasts are intended for a general audience and required to be less than 3 minutes.
Posted by Kevin Judd at 12:50 PM
Printable Version | Link to this page
Comments
Comments 1 to 23:
1. cruzn246 at 13:15 PM on 22 September, 2010There is no upswing in extreme weather.
2. Phila at 13:37 PM on 22 September, 2010#1 cruzn246
This is a science site. Please present compelling evidence when you make claims, so that we'll know why we should listen to you instead of, say,Thomas Karl, or the World Meteorological Association.
3. ScruffyDan at 14:59 PM on 22 September, 2010Is there a rss feed for the climatecast?
Response: RTR FM have a podcast page but not specifically for the fortnightly climate podcast. If people are interested, I could ask the UWA folk whether it would be possible to host their audio recordings on Skeptical Science.
4. jyyh at 15:31 PM on 22 September, 2010A suddenly appearing, prolonged 2-3 degrees rise of the ambient temperature in humans leads to a situation where the individual in question normally goes to a doctor.
5. jsam at 16:17 PM on 22 September, 2010cruzn246 - "Record High Temperatures Far Outpace Record Lows Across U.S.". And this is up to 2009 - 2010 is even warmer. http://www.ucar.edu/news/releases/2009/maxmin.jsp#
6. MattJ at 17:03 PM on 22 September, 2010A good article. It is kind of curious to note, however, that for those of us who do not know RFR FM is an Australian station, the only clue that the text was written for Australians is the .au suffix in the URL (there are other cities named 'Perth' -- such as in Scotland).
This is relevant, since there are other points in the article that are much clearer once you realize it was written for an Australian audience. The use of unadorned numbers for temperatures in degrees Celsius is a prominent example.
Remember you WANT more Yanks reading your articles! But for us, 'degrees' measuring temperature as assumed Fahrenheit unless we are told otherwise. 2-3 degrees Fahrenheit really is small. But we can easily see 2-3 degrees Celsius as much more significant.
I suggest the site deal with this problem by the use of the common convention of putting explanatory text, text not in the original transcript (since this was broadcast over the radio) in square brackets. So, for example, "rise 2 to 3 degrees" becomes, "rise 2 to 3 degrees Celsius". Likewise, 'Perth" becomes, "Perth, Australia".
7. Roger A. Wehage at 18:14 PM on 22 September, 2010Perhaps the following question might be more pertinent, "Does the dog wag the tail or the tail wag the dog?" Suppose that both are possible. Then the next question might be, "Could they ever occur simultaneously, and if they did, what would be the consequences?" "Scientists" believe that tail wagging indicates a state of conflict. People believe that happy dogs wag their tail, but many "happy dogs" have bitten people. This leads to the possibility that the tail may be wagging these "happy dogs," which makes them mad, so they bite you. Since a dog can't both be happy and mad at the same time, it is impossible that the dog is wagging the tail and the tail is wagging the dog at the same time. So there you have it.
But what if a 2-3 °C rise in global temperature were to cause some weird change in a dog's disposition, such that it can be both happy and mad at the same time? Now the dog can wag the tail and the tail can wag the dog at the same time. That has never before been seen in nature, so no one knows what the outcome will be. Think what would happen to the poor dog if simultaneous dog wagging tail and tail wagging dog were to cause a "Positive Feedback."
Now I don't believe in God, so I tend to think that man was not created in His image and can therefore become extinct, just as easily as any other "animal."Unless man can devise a way to live happily ever after with giant clouds of methane burbling up from the ground and oceans, he ought to be taking more seriously prospects of the "Day of Judgement."
8. Arkadiusz Semczyszak at 21:22 PM on 22 September, 2010“Big storms and extreme weather require a lot of energy to drive them.”
Nothing could be further from the truth. Great storms require a considerable variation in energy over a small area.
The violent weather phenomena occur in the specified temperature range. Hence warming - only if in a strictly defined temperature range - will increase the number of extreme events. The same cooling.
This explains the theory of fluid mechanics. On the surface hydrophobic water droplets combine (and simultaneously disconnect) rapidly only in the specified temperature range. The increase in temperature causes the droplets merge is declining, growing up (more "lazy") drops consisting of several smaller drops. They join fewer and much milder.Also, if we treat the global atmospheric circulation as a cybernetic system, we understand that with the increase of the energy supply to such an system, he will be able to run additional feedbacks stabilizing system - number of extreme events as a result of warming MUST be reduced.Polish scientists (Natural Disasters, 2008.) write: "In the years 1701-1850, ie during the period when the Earth was in the so-called Little Ice Age in the Caribbean basin hurricanes were almost three times higher than in the second half of last century, and from 1851 to 1950 - twice as frequent. [!!!] Total number of tropical cyclones on Earth in the twentieth century, was twice smaller than in the nineteenth century [!!!]"In periods other former cooling (8-8,3; 5,1-5,7, 4.5 ≈ 2.1, and 2-1,6 thousand years ago) has always followed a significant increase in strength of ENSO - tropical cyclones ...In the United States during the beginning of Dalton minimum in 1780, the largest ever recorded in the so-called. "Great Hurricane" (much stronger than Hurricane Katrina) killed at least 22,000 people ...
Currently, when the estuaries are much more densely populated ...
Rising temperatures have already by 1.5 ° C will reduce the frequency of high-pressure system (anticyclones), the extension of the troposphere. Compared with the current temperatures, will reduce pressure gradient in the atmosphere, also lose their importance as barriers to the mountains. Beautifully seen an example of the Sahara. In the summer there are only shallow low-pressure systems, but only in winter powerful, stationary anticyclones (indeed, as in Siberia).Phenomena in the atmosphere does not occur linearly. Currently, Hadley cell expands. As a result of warming of 3-4 ° C, as always, extend, however, (on N and S) Ferrell cell. Hadley cell may even disappear - like cell zone separating the two areas of high pressure (the same way as - described above - in the summer in the Sahara).
Heat waves in the NH (2003, 2006, 2010) are associated more with violent beginnings of La Nina - cooling of the oceans, fewer algal NPP - cloudiness (CLAW hypothesis).
Global warming and United States landfalling hurricanes, Wang and Lee, 2008.: “Warmings over the tropical oceans compete with one another, with the tropical Pacific and Indian Oceans increasing wind shear and the tropical North Atlantic decreasing wind shear. Warmings in the tropical Pacific and Indian Oceans win the competition and produce increased wind shear which reduces US landfalling hurricanes.” The authors also say:
“This paper uses observational data to demonstrate that the attribution of the recent increase in Atlantic hurricane activity to global warming is premature and that global warming may decrease the likelihood of hurricanes making landfall in the United States.”“The accumulated cyclone energy index, which has been used to measure tropical cyclone activity, is also observed to have a downward trend for global hurricanes over the past two decades when consistent satellite imagery has been available.”
May vary regionally (IV IPCC report and „... the North Atlantic to warm more slowly than other oceans ...” - weakening of the AMOC - cooling of the North Atlantic) and the gradient of "vertical wind shear" may rise.
However, declining globally (with warming) gradient of "vertical wind shear" decides to lower the intensity and frequency of all storms, not just the big.
9. Byron Smith at 23:50 PM on 22 September, 2010The effects you are most likely to experience is an increase in extreme weather.Actually, might it not be more likely that the effects most readers (who will be more likely to come from relatively rich developed countries with more moderate climates) will be the knock on effects of extreme weather elsewhere, experienced as economic turbulence and the political effects of food insecurity. But hard to know exactly what is going to hit a given person personally first. Some may experience extreme weather directly, but I suspect that many more will face knock on consequences of declining food production. That is, climate change will probably affect many people in ways that they don't think of as due to climate change, but it will be one of the significant background causes.
@Roger A. WehageNow I don't believe in God, so I tend to think that man was not created in His image and can therefore become extinctI do believe in God and tend to think that humanity was created in God's image, but I also think that we can become extinct. There is no divine promise of personal or civilisational protection.
10. Daniel Bailey at 00:06 AM on 23 September, 2010Re: cruzn246 (1)
"There is no upswing in extreme weather."
Your Jedi mind tricks won't work on us here.
The Yooper
11. Rob Honeycutt at 01:56 AM on 23 September, 2010There's a minor grammatical error in the second to the last paragraph. I believe that would be "affected" not "effected."
12. John Bear at 04:21 AM on 23 September, 2010I agree with Mr. Judd’s argument. As Matt J. (comment 6) pointed out, 2-3 degrees Celsius is equivalent to 4-6 degrees Fahrenheit. An increase in several degrees might seem minute at first, but one needs to consider the scale upon which we are viewing these changes. Consider the human body for example. Our body’s hold a general temperature of around 98.6 degrees Fahrenheit; with a less than a two degree increase in our body’s core temperature we are classified as having a fever, entering a state of “sickness.” Now I know our bodies are different than the entire world; or, are they really that much different? The nature of the planet we live in is in no way less intricate than the incredible complexity of our
bodies; both exist in a delicate balance. Countless systems work together in harmony under an ideal set of conditions. If the conditions in which these systems operate are altered even slightly, the consequences can be exponential. If you have a fever and catch a cold, are you able to operate at your normal day-to-day level? Now consider Earth “catching a cold,” the symptoms of our planet getting sick can be devastating not only now, but for future generations to come.
13. The Ville at 05:18 AM on 23 September, 2010Kevin Judd:“Big storms and extreme weather require a lot of energy to drive them.”
Arkadiusz Semczyszak response"Nothing could be further from the truth. Great storms require a considerable variation in energy over a small area."
The Ville:Tell us something we don't know Arkadiusz.Since Kevin didn't actually define what a big storm was, I think you are making an assumption and then automatically correcting something without knowing what Kevin was referring to.If you weren't here to be deliberately negative, you would have asked for a clearer definition of what a big storm was and then made a comment on that.
Arkadiusz Semczyszak:"...we understand that with the increase of the energy supply to such an system...number of extreme events as a result of warming MUST be reduced."
The Ville:By your own definition you are incorrect. You earlier stated "Great storms require a considerable variation in energy over a small area.", not increased or decreased energy.
Arkadiusz Semczyszak:"Polish scientists (Natural Disasters, 2008.) write: "In the years 1701-1850, ie during the period when the Earth was in the so-called Little Ice Age in the Caribbean basin hurricanes were almost three times higher than in the second half of last century."
The Ville:Sorry, 'Polish scientists' were cherry picking or wildly wrong.See Ricardo García-Herreras work on Spanish records of hurricanes in that area and era. Given that the Polish were no where to be seen as far as Atlantic exploration is concerned, I think Spanish records are probably more accurate. Specifically between 1576 and 1601 there was a huge peak, they then dipped until 1760, then started peaking again. eg. during a large chunk of the 'LIA' there were both larger numbers and fewer.
14. Arkadiusz Semczyszak at 19:18 PM on 23 September, 2010“By your own definition you are incorrect.”
No. At the hydrophobic surface sufficiently heated, drops generally do not combine - do not join because they do not ... The liquid forms a uniform layer. Violent phenomena virtually disappear. That's why (among other things + no Panamanian isthmus) in the Oligocene tree ferns (with extremely fragile stems) grew almost from the equator - practically to the North Pole - around - so defined area - and in addition, the same species.
15. ianw01 at 23:46 PM on 23 September, 2010I find this post disappointing for its lack of data to support the premise that warming will drive more extreme weather events. Where are the peer reviewed papers, statistically significant trends, and large (not cherry-picked) data sets?
In the absence of any supporting data, articles like this discredit the generally solid scientific story behind global warming. Furthermore, it provides fodder for the distractions that deniers tend to latch onto.
I'm not saying it is or isn't true, but the lack of data or references is a red flag. In the absence of any data, I could argue that greater warming in the polar regions will result in smaller temperature gradients in general, and therefore less extreme weather. (Don't anyone get worked up - it is just to make a point about the need for evidence.)
Sure, the post is a podcast, but the bar must be set higher for inclusion on this site.
Response: It was for this reason that Kevin asked me to specifically mention this was a transcript of a very short message for a broad audience. Kevin is probably the only climate scientist I know whose public communications are accused of being too simple (and I'm not sure he's a big fan of that fact). Other posts on extreme weather such as the page about record snowfall and extreme precipitation events feature many peer-reviewed references. However, currently there is a diverse range of styles on offer at Skeptical Science - both basic, light pieces and detailed, technical articles. It is all part of a plan :-)
16. The Ville at 03:38 AM on 24 September, 2010Arkadiusz you haven't responded to a remark I have made. It doesn't even relate to your own previous comment. Instead you have gone off in some unrelated tangent.
17. Badgersouth at 04:01 AM on 24 September, 2010The carbon dioxide emissions from burning fossil fuels have melted the Arctic sea ice to its lowest volume since before the rise of human civilisation, dangerously upsetting the energy balance of the entire planet, climate scientists are reporting.
"The Arctic sea ice has reached its four lowest summer extents (area covered) in the last four years," said Mark Serreze, director of the National Snow and Ice Data Center in the U.S. city of Boulder, Colorado.
The volume - extent and thickness - of ice left in the Arctic likely reached the lowest ever level this month, Serreze told IPS.
"I stand by my previous statements that the Arctic summer sea ice cover is in a death spiral. It's not going to recover," he said.
Source: “Arctic Ice in Death Spiral,” IPS, Sep 20, 2010
http://ipsnews.net/news.asp?idnews=52896
I encourage everyone perusing this comment thread to read this article in its entirety.
The predictied changes to the Arctic climate system that is already built into the system will have profound effects on the global climate system.
"Heat waves in the NH (2003, 2006, 2010) are associated more with violent beginnings of La Nina - cooling of the oceans, fewer algal NPP - cloudiness (CLAW hypothesis). "
Only 2010 was begining of "violent" La Nina as i think.http://www.cpc.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml
19. ianw01 at 23:42 PM on 24 September, 2010Thanks, John, for the reply regarding data supporting extreme weather. The link and references therein were helpful.
But still, we must be careful about attributing too many weather events to global warming, without solid evidence. In my view it is one of the weakest aspects of the "alarmist" positions.
20. archiesteel at 01:11 AM on 25 September, 2010@ianw01: that's why it's always safer to say that an increase in extreme weather events is "consistent" with AGW theory.
21. johnd at 09:52 AM on 25 September, 2010ianw01 at 23:42 PM, all weather events, extreme or otherwise, are driven by the same combination of a heat differentials and moisture, and they all unfold the same way.
As the water vapour picked up rises, it gradually releases heat, condensing out forming different cloud types in sequence until finally the air becomes dry above where cirrus clouds are the last to form.
The albedo effect dominates the low altitude clouds, so they then provide a nett cooling effect to the Earth's climate.However uncertainty remains about the high level cirrus clouds, which alone cover about 35% of the earths surface, but as this passage from a CLOUDSAT overview would indicate, linking extreme weather events with climate change is treading on uncertain ground as you noted.
(http://cloudsat.atmos.colostate.edu/overview)"Because clouds have such a large impact on Earth’s radiation budget, even small changes in cloud abundance or distribution could alter the climate more than the anticipated changes in greenhouse gases, anthropogenic aerosols, or other factors associated with global change. Changes in climate that are caused by clouds may in turn give rise to changes in clouds due to climate: a cloud-climate feedback. These feedbacks may be positive (reinforcing the changes) or negative (tending to reduce the net change), depending on the processes involved. These considerations lead scientists to believe that the main uncertainties in climate model simulations are due to the difficulties in adequately representing clouds and their radiative properties."
22. doug_bostrom at 10:04 AM on 25 September, 2010Shorter johnd: More convection will manifest itself invisibly.
Climate scientists respond to Monckton's misinformationOn May 2010, Christopher Monckton testified to the U.S. Congress, where he argued there was no need to take quick action to address climate change. Monckton made a number of assertions about CO2 warming, the benefits of elevated CO2, ocean acidification, temperature trends and climate sensitivity. Recently, a group of 5 scientists solicited responses to Monckton's testimony from more than 20 world-class climate scientists. Each climate scientist examined the part of Monckton's testimony related to their particular area of expertise and summarised their responses in the report Climate Scientists Respond. The result is thorough, methodical and devastating. Monckton’s assertions are shown to be without merit, demonstrating a number of obvious and elementary errors and based on a thorough misunderstanding of the science.
Climate Scientists Respond refutes Monckton's testimony in 9 major areas.
1. Monckton misunderstands how carbon dioxide (CO2) played a role in lifting the Earth from a cold 'snowball' state, treating the events as if they were contemporaneous.
2. He incorrectly argues that the present rapid increase in CO2 is harmless to coral, ignoring the vast difference in the rate of change of CO2 levels compred to millions of years ago
3. Monckton claims a single benefit of higher CO2 levels – increased yields on selected crops – but fails to mention the wide-ranging negative consequences for plant species and agriculture.
4. Monckton's claim that CO2 is not causing ocean acidification provide a compelling example of his lack of understanding of ocean chemistry.
5. Despite Monckton’s assertions, compilations of global temperatures show that the late 20th century was exceptionally warm compared with the last 1500 years, with an exceptional rate of warming.
6. His assertion that 'global warming ceased in 2001' is contradicted by recent, record-breaking global mean temperatures.
7. Monckton ascribes the recent rise in global temperature to global brightening, citing a 2005 paper by Dr. Rachel Pinker. As the responses demonstrate, and indeed as Dr. Pinker herself has stated, his conclusions are based on a misunderstanding and misapplication of that work.
8. Monckton argues climate sensitivity is low, based on his misinterpretation of the Pinker paper, as well as on a recent paper by Lindzen and Choi. Two recently published papers discussed in this report thoroughly discredit the paper by Lindzen and Choi, as well as Monckton’s conclusions.
9. Monckton argues that “global warming is a non-problem”, and the correct response is “to do nothing”. This report states that a “decision to delay action to reduce greenhouse emissions is not a decision 'to do nothing'. It is a decision to continue emissions of CO2...committing the world to higher levels of global warming...with associated adverse impacts.”
As you read through the document, it becomes apparent why so many scientists were involved in this effort. For each of Monckton's claims, there are responses from a number of different scientists. The striking feature is each scientist addresses and explains a different error. Monckton's testimony is so riddled with errors, it takes a number of scientific expert to debunk all the disinformation!
This is an immensely useful, fascinating and important document. I would strongly recommend to any place where Monckton is public speaking that copies of this document are handed to the people attending the talk. I have one criticism. Why wasn't this done years ago?
Scientists who contributed to Climate Scientists Respond 1. Dr. James Annan: Member of the Global Change Projection Research Program within the
Research Institute for Global Change2. Dr. David Archer: Professor, Department of Geophysical Sciences, University of Chicago3. Dr. Ken Caldeira: Senior Scientist, Department of Global Ecology, Carnegie Institution,
California4. Dr. David Easterling: Chief, Scientific Services Division, NCDC, National Oceanic and
Atmosphere Administration (NOAA)5. Dr. James Hansen: Director, NASA Goddard Institute for Space Studies6. Dr. Ove Hoegh-Guldberg: Professor of Marine Studies, University of Queensland, Australia.7. Dr. James Hurrell: Senior Scientist in the Climate Analysis Section and Chief Scientist for
Community Climate Projects at the National Center for Atmospheric Research, Boulder, Colorado
8. Dr. David Karoly: Professor, School of Earth Sciences, University of Melbourne, Australia9. Dr. Jeffrey Kiehl: Senior Scientist, Climate Change Research Section, National Center for
Atmospheric Research, Boulder, Colorado10. Dr. Nancy Knowlton: Holds the Sant Chair in Marine Science at the Smithsonian’s National
Museum of Natural History11. Dr. Lee Kump: Professor of Geosciences, Pennsylvania State University12. Dr. Norman Loeb: scientist at the NASA Langley Research Center13. Dr. Michael MacCracken: Chief Scientist, Climate Change Programs with the Climate
Institute in Washington DC14. Dr. Peter Reich: Regents Professor and Distinguished McKnight University Professor,
University of Minnesota’s Department of Forest Resources15. Dr. Reto Ruedy: Scientist at the NASA Goddard Institute for Space Studies16. Dr. Benjamin Santer: Research Scientist, Program for Climate Model Diagnosis and
Intercomparison (PCMDI), Lawrence Livermore National Laboratory17. Dr. Gavin Schmidt: Climate Scientist, NASA Goddard Institute for Space Studies18. Dr. Pieter Tans: Senior Scientist, NOAA Earth System Research Laboratory, Boulder,
Colorado19. Dr. Kevin Trenberth: Senior Scientist and Head, Climate Analysis Section at the National
Center for Atmospheric Research, Boulder, Colorado20. Dr. John Veron: Professor, University Center for Marine Studies, University of Queensland21. Dr. Bruce Wielicki: Senior Scientist Radiation Sciences, NASA Langley Research Center
The five scientists who organized the report were: Drs. Ray Weymann, Barry Bickmore, John Abraham, Michael Mann and Winslow Briggs.
Climate Scientists Respond: the full PDF report
Press Release
UPDATE 22/9/2010: The UK Guardian published an article about Climate Scientists Respond. Monckton sent a characteristically unhinged reply where he labels the climate scientists as either
criminal, serial liars, mentally disable or having had their emails stolen in Climategate (good to see he still eschews ad hominem attacks). Barry Bickmoreresponds to Monckton's response.
Personal prediction: Monckton will follow this up in a few weeks with another Monckton Gallop of hundreds of questions.
Posted by John Cook at 02:20 AM
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Comments
Comments 1 to 42:
1. Anne-Marie Blackburn at 02:33 AM on 22 September, 2010I will never understand why Monckton was allowed to testify to the US Congress since it's been clear for some time that he doesn't know what he's talking about.
Look forward to reading to the report.
2. Albatross at 02:37 AM on 22 September, 2010This is fantastic news!
In fact, it made my day.
3. Daniel Bailey at 02:58 AM on 22 September, 2010Long overdue. Thanks!
The Yooper
4. dana1981 at 03:07 AM on 22 September, 2010That list of 21 climate scientists has some very impressive names. It's just too bad they have to waste their time debunking Monckton's nonsense.
5. beam me up scotty at 03:16 AM on 22 September, 2010Here's a nice presentationhttp://www.stthomas.edu/engineering/jpabraham/
6. mehus at 03:48 AM on 22 September, 2010This is a fantastic rebuttal using a who's who of climate change science. I can only imagine the response from Monckton. His head might just explode. If he issued over 400 question to Dr Santer from his presentations I can only imagine how long and delusional his rebuttal to this will be. That task may keep Monckton busy for another year or two...
7. paulm at 03:58 AM on 22 September, 2010Climate scientists respond to WHO?
Will it be sent to the committee?
Will they revise their conclusions?
Why is this hind sight?
8. Alexandre at 04:05 AM on 22 September, 2010I kinda share John's criticism, but let's not be grumpy. I hope this is the first of a long row of public statements from climate scientists.
Misinformation has been spread long enough without proper response.
9. BillWalker at 05:03 AM on 22 September, 2010I hope they're sending a copy of this to every member of Congress.
10. tobyjoyce at 05:05 AM on 22 September, 2010I note a careful "dissing" of the egregious Lord. He is generally referred to as "Monckton" without the title.
I hope the US politicians get the subtle message that they should be talking about science to scientists, not publicists.
11. rab at 05:16 AM on 22 September, 2010Note the last sentence on the cover page: "We encourage the U.S. Congress to give careful consideration to the implications this document has for the care that should be exercised in choosing expert witnesses to inform the legislative process".
The US scientists present at the hearing must have profoundly embarrassed that their Congress had invited what amounts to a "climate quack" to give testimony. It would be like inviting a homeopathic practitioner to testify at a hearing on healthcare.
12. SouthWing at 06:44 AM on 22 September, 2010@1 Anne-Marie Blackburn I will never understand why Monckton was allowed to testify to the US Congress since it's been clear for some time that he doesn't know what he's talking about.
Then, alas, you will never understand the sheer venality of American politics.
It matters not a bit to his Republican denier sponsors that Monckton is a mendacious blowhard; he says the things they want to hear, so he is given a pulpit.
13. Rob Honeycutt at 07:17 AM on 22 September, 2010This is fantastic. It's great these scientists have taken time from their busy lives to do this. It's so incredibly important.
I watched a video clip the other day of Monckton debating a climate scientist in AU on some news program (not sure which one now). It was fascinating. Once the climate scientist started to point out his inaccuracies Monckton reverted to talking over everything that anyone said including the interviewer. Almost meaningless and rambling stuff barely related to the issue.
He really seems to be genuinely driven by paranoia of a global neo-nazi conspiracy where science is somehow at the center of it all. I'm sure that's now he will receive this report.
14. The Ville at 07:31 AM on 22 September, 2010Alexandre@8:"I hope this is the first of a long row of public statements from climate scientists."
Oh I hope not.They waste enough time already rebutting Monckton.That's just what he wants.
15. Rob Honeycutt at 07:47 AM on 22 September, 2010Actually, The Ville, I don't think Monckton takes well to criticism. Do you remember the outrageous responses he made to Dr Abraham's presentation? The least of which was calling him a "boiled prawn."
That was one professor from a small college. This is 21 climate scientists with considerable reputations to back up their assertions. Monckton will surely take this as a frontal attack on his reputation.
Expect a number of Fox News interviews to follow shortly.
Who's making the popcorn?
16. Alexandre at 08:21 AM on 22 September, 2010The Ville #14
You have a point there... but this nonsense has lasted long enough. I don't know how long it took for those great scientists to write that text, but it's well worth to drop a line to the broader public now and then and make the message clear.
I hope they won't have to do this again. But I sure hope they'll do it again if needed.
17. Anne-Marie Blackburn at 08:35 AM on 22 September, 2010SouthWing - I live in the UK and don't have much knowledge of US politics, though I'm learning much about it through debates on climate change and creationism. A system that allows unqualified people such as Monckton to testify on highly technical topics baffles me. Completely. I understand that it's a political battleground but it's going to take me some time to get used to such an absurd system.
18. CoalGeologist at 09:17 AM on 22 September, 2010In response to the question “Why wasn't this done years ago?”, there are several responses.
For one, I don’t believe the scientific community took the "skeptical" criticisms seriously enough. More specifically, I think they [mis-]underestimated the degree to which contrarian views would dominate the scientific debate. This situation has now changed, and this report is evidence of that.
Secondly, each of these distinguished scientists has his/her own career to pursue, requiring a very substantial investment of time and effort. Who has the time to write a response to someone so uninformed on the scientific issues? This partly comes down to a question of priorities, and in this regard, there is little prestige and recognition to be gained by publishing outside the traditional “peer-reviewed” journals. This too must change. The scientific community must roll up their collective sleeves, and get their message out. SkS is very much in tune with this goal, but will the authors of this report get adequate recognition from their administrators and home institutions. Here, SkS readers can potentially play a useful role, through thoughtfully worded letters of support sent to the appropriate institutions.
Thirdly (although of much less significance), we all need to get involved, at no matter what
level, and not allow the most strident voices to dominate. I actually initiated a minor effort back in October, 2008 to respond to a three-part article by Lord Monckton published in the dubiously titled journal “The American Thinker”. I went as far as to solicit comments from several prominent climate researchers, but ultimately, nothing came of it, owing partly to the challenges described above, partly to the overwhelming number of errors in the article, and partly to my "dropping the ball". The point of this “mea culpa” moment is that each of us has a duty to speak up on behalf of science, and not sit back and assume that reason will prevail.
19. adelady at 09:31 AM on 22 September, 2010CG, your stomach is stronger than mine. American Stinker is an awful place, I commend you for giving it a go.
As for the scientists initially 'weak' dealings with the sceptics. I think everyone was a bit misled by the success of the campaign to reduce sulphate emissions because of the obvious impacts of acid rain. At the outset, with the formation of the IPCC, it looked as though it was going to go along the same path.
Tedious hard work, long negotiations, eventual agreement, implementation.
And now we're debating the physics of gases over and over and over again. With people who've been misled by the likes of Monckton and others wilfully conflating the issue with the Catastrophic Financial Meltdown alarmist nonsense.
20. MattJ at 09:46 AM on 22 September, 2010Why wasn't it done years ago? Good question. It was important enough that it should have been done years ago. But it took a lot of work. No doubt that has a lot to do with why it was left undone for too long.
But this is characteristic of Monckton's bad behavior: he strings together a lot of pseudo-scientific statements, each one of which sounds vaguely plausible to both Congressman and layman, and then states his conclusion very forcefully.
Unfortunately, people really are heavily inclined to believe statements framed that way: scientists seem to forget what long training it took to get -them- out of the habit of doing so!
So the result is that it takes only a little bit of work on Monckton's part to persuade the misinformed, but it takes much, MUCH more work to rebut him. No wonder his side has been winning for so long.
21. ProfMandia at 10:01 AM on 22 September, 2010To my fellow Americans:
Write to your elected officials and ask them to investigate Monckton and to consider if they believe he committed perjury. You can locate your Reps and Senators at USA.gov
After doing that, consider writing to the top medial outlets. I have a lengthy list here.
Do not be content to just applaud on a blog.
22. Albatross at 10:17 AM on 22 September, 2010Re #21,
Thanks Scott. Good points-- people need to be proactive. Those letters are not ignored and I have been told that, in my country at least, letters carry a lot of wait, especially nowadays.
23. Agnostic at 10:28 AM on 22 September, 2010Rob Honeycutt @ 15 ….”Expect a number of Fox News interviews to follow shortly”
Well, maybe. My guess is that while the Murdoch media is willing to give Monckton a free pulpit from which to spew his nonsense, the wily and mischievous Murdoch will not publicly support Monckton’s views. Murdoch knows, as we all should by now, that anything Monckton says on global warming, climate change or its other effects, is wrong.
My only quibble with Monckton’s critics is that they accuse him of misunderstanding science. He does not misunderstand, he deliberately and knowingly misrepresents.
24. oslo at 12:51 PM on 22 September, 2010New important study announced (NOAA):
Scientists Find 20 Years of Deep Water Warming Leading to Sea Level Rise
It should debunk Pielke Sr. new spin on the matter:
New Paper “Recent Energy Balance Of Earth” By Knox and Douglas 2010
Oh, and it might prove the new Antarctic / Greenland ice loss study correct?
25. Albatross at 13:34 PM on 22 September, 2010Oslo @24,
Thanks for the heads up. This is OT of course, but let us not forget the dismal Douglass et al. (2007)--which was co-authored with Singer-- before we give their findings too much weight.
I have infinitely more faith in the UofW research that you linked to. That "missing" heat, it appears, is working its way down much deeper than thought-- quelle surprise.
26. oslo at 13:40 PM on 22 September, 2010I already had Douglas looked up ;-)
Sorry to be OT, but it seemed important in context with the new article at Pielkes Sr. blog.
27. CBDunkerson at 23:02 PM on 22 September, 2010Ken #27, yes Monckton is just an eccentric extremist... who climate skeptics chose to represent their position before the US Congress.
As to 'why people would oppose false views arguing against dealing with a dangerous problem'... gee that's a tough one.
28. Jeff T at 01:34 AM on 23 September, 2010Re #21 (ProfMandia) and #22 (Albatross). Can we please stay away from recommending criminal prosecution? It may be justified, but it makes us too similar to the Attorney General of Virginia threatening Michael Mann. Let's stick to the science.
Until not too long ago I would have agreed with you Jeff. But, IMHO, when appropriate, we now have to fight fire with fire. If compelling evidence exists of perjury, then surely as law abiding citizens we should not let such acts go unchallenged?
Taking Monckton to task is not the same as the "witch hunt" undertaken by the Virginia AG. I hope that you can see the huge difference not only in terms of evidence, but motives to, in the case of Monckton. This is a very different kettle of fish.
I agree that one should stick to the science, hence my delight that the scientists took the time and effort to counter Monckton using facts. Additionally, Monckton has been debunked so many times to no avail. So, IMO, suggesting that scientists are not permitted to take legal action when warranted, and nor should that be frowned upon, is not fair nor reasonable. Why should someone be given free pass in the event that they committed perjury?
Taking the high road does not mean that we have to check our principles and justice system at the door.
30. Albatross at 02:51 AM on 23 September, 2010Rob @34,
I fear that John might edit this as it is OT, but I want to clarify something before letting everyone move on.
The Virginia AG did not have grounds to investigate Mann, nor was it a legitimate action-- he was clearly on a witch hunt and fishing for something. In contrast, committing perjury is actionable and there is compelling and legitimate evidence to make that case here.
31. Rob Honeycutt at 03:40 AM on 23 September, 2010Albatross... Also sorry if we're going OT. I could be wrong but I think the AG probably can file a case regardless of whether it has grounds or not. And that's what happened. The case was completely without merit and was struck down by the judge.
Literally, I think Cuccinelli was just trying to make noise in order to raise his own profile in politics. In that, the case didn't need to have any merit at all. It's just grandstanding for attention. For Cuccinelli it was mission accomplished.
32. Albatross at 03:47 AM on 23 September, 2010Rob @36,
No need to apologise to me, I'm just concerned that we are distracting from the point of the post-- that said, I do now feel obligated to answer questions asked of me. Hope John is not grumpy when he wakes up (;
I'm sure that an AG can file a case whenever he or she chooses to (maybe I was not clear on that), but to do so without sufficient grounds is probably not good for one's career ;)
33. Rob Honeycutt at 04:03 AM on 23 September, 2010Albatross... Yeah, I'm sure as soon as John gets up we're both busted. ;-)
Sometimes I think we're living in upside down world in US politics today where doing stupid things can actually propel your career.
34. Albatross at 04:11 AM on 23 September, 2010Hi Rob @38,
"But Dr. Scott Mandia started it!"-- says the albatross pointing a huge wing at post #22.
Seriously though, I think some politicans have borrowed a page from Hollywood-types in terms of antics used to "advance" their careers.
Hmm, I have a self imposed deadline to meet and am clearly procrastinating.
35. snapple at 09:05 AM on 23 September, 2010The Guardian still doesn't have a working link to this article.
Look, the politicians are getting a lot of money from fossil fuel interests.
Cuccinelli's dad used to work in marketing for the American Gas Association and now has two companies that do advertising and marketing--including for "European" companies.
Sometimes these "professional services" are just ways of laundering money from foreign entities to US politicians.
I have some experience of such "Europeans." They are going to try to destroy the scientists by hiring politicians and lawyers. They are going to take over consumer affairs. That's what they do in the part of "Europe" they come from.
They don't care what is true. They want to sell gas.
36. Philippe Chantreau at 02:00 AM on 24 September, 2010Climate skepticism is like the Gold Rush. There is so little gold to be had that it's truly not worth the effort. But then there are the clever ones, who do the cooking and the laundry and sell the booze to the miners. They're the ones getting rich. There are some very clever climate skeptics out there cashing in on the rush. Steven Mosher with his climategate book. Loehle, who wrote a book titled, believe it or not, "How to be a successful scientist." Yep, from the guy whose publication record is (almost?) exclusively in E&E...Then there is Watts, and all the ads he gets on his site, plus the exposure transferred to his electric car project. And Monckton with his speech tour. They're all working hard for the miners and raking in the dough.
Quit wasting your time on a blog Ken, there is a large public out there ready to pay you to continue telling them what they want to hear. No data analysis required, no fancy statistics, no headache-generating line by line radiative transfer model, no Rossby Waves, just some good ol' talk in a book with a shocking title. Have at it, it's free money.
37. Roger D at 13:06 PM on 24 September, 2010An insignificant point really to Dr. Verons response to Monckton's faulty logic; but on page 5 of Climate Scientists Respond there is the statement by Dr. Veron: "There were no corals in the Cambrian, symbiotic or otherwise: they had not evolved then."
Maybe I'm missing something but some seemingly reliable internet sites state that corals did exist in the Cambrian. Maybe I'll have to dig out that 25 year old Historical Geology text.
Anyway, a devastating rebuttal to Monckton. Cheers!
38. Rob Honeycutt at 01:12 AM on 25 September, 2010Roger... I believe solitary corals developed in the Cambrian but reef forming corals came about in the early Ordovician.
39. Roger D at 12:30 PM on 25 September, 2010Thank you Rob re: @38. - that makes sense.Also - Thanks John C for the website
40. CoalGeologist at 00:35 AM on 26 September, 2010I've learned from an informed source that at hearings on "Extreme Weather in a Warming World" held two days ago (Thurs., 23-Sep), convened by the U.S. House Select Committee on Energy Independence and Global Warming that one Committee member requested that the scientists' rebuttal of Monckton be entered into the official record.
The importance and value of this document is that it directly addresses Monckton's arguments, without requiring people who are less well grounded in the scientific evidence to juxtapose this evidence on their own. Bravo, again, to the climate scientists who worked on this.
By the way... This led me to an interesting and potentially valuable information resource related to climate change I hadn't seen previously, providing a compilation of testimony presented before the Committee, plus lots of other multi-media resources. Nothing posted yet from Thursdays hearings.
41. CoalGeologist at 00:53 AM on 26 September, 2010UPDATE: Unless I missed it the first time, the hearing proceedings have just been posted: http://globalwarming.house.gov/pubs?id=0023#main_content
42. Daniel Bailey at 01:14 AM on 26 September, 2010Re: CoalGeologist (40,41)
Thanks for posting the links. I pulled this statement out of the Opening Statement by Representative Edward J. Markey, Chairman of the Select Committee on Energy Independence and Global Warming:
"Meanwhile, concentrations of heat-trapping pollutioncontinue to rise in our atmosphere, committing us to further warming in the decades ahead."
Strong statement from a politician.
Thanks again!
The Yooper
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Risky Business: Gambling on Climate SensitivityThere are some things about our climate we are pretty certain about. Unfortunately, climate sensitivity isn’t one of them. Climate sensitivity is the estimate of how much the earth's climate will warm if carbon dioxide equivalents are doubled. This is very important because if it is low, as some sceptics argue, then the planet isn’t going to warm up very much. If sensitivity is high, then we could be in for a very bad time indeed.
There are two ways of working out what climate sensitivity is (a third way – waiting a century – isn’t an option, but we’ll come to that in a moment). The first method is by modelling:
Climate models have predicted the least temperature rise would be on average 1.65°C (2.97°F) , but upper estimates vary a lot, averaging 5.2°C (9.36°F). Current best estimates are for a rise of around 3°C (5.4°F), with a likely maximum of 4.5°C (8.1°F).
The second method calculates climate sensitivity directly from physical evidence:
These calculations use data from sources like ice cores, paleoclimate records, ocean heat uptake and solar cycles, to work out how much additional heat the doubling of greenhouse gases will produce. The lowest estimate of warming is close to the models - 1.8°C (3.24°F ) on average - but the upper estimate is a little more consistent, at an average of around 3.5°C (6.3°F).
It’s all a matter of degreeTo the lay person, the arguments are obscure and complicated by other factors, like the time the climate takes to respond. But climate sensitivity is not just an abstract exchange of statistics relevant only to scientists. It also tells us about the likely changes to the climate that today's children will inherit.
Consider a rise in sea levels, for example. Predictions range from centimetres to many metres, and the actual increase will be governed by climate sensitivity. The 2007 IPCC report proposed a range of sea level rises based on different increases in temperature, but we now know they underestimated sea level rise, perhaps by a factor of three, in part because of a lack of data about the behaviour of Greenland and Antarctic ice-sheets.
Current estimates of sea level rise alone, as a result of a two degree rise in temperature, are very worrying. More worrying is that the current projections do not account for recently accelerated melting of polar regions. There are also many other possible effects of a 2°C rise (3.6°F) that would be very disruptive.
All the models and evidence confirm a minimum warming close to 2°C for a doubling of atmospheric CO2 with a most likely value of 3°C and the potential to warm 4.5°C or even more. Even such a small rise would signal many damaging and highly disruptive changes to the environment. In this light, the arguments against mitigation because of climate sensitivity are a form of gambling. A minority claim the climate is less sensitive than we think, the implication being we don’t need to do anything much about it. Others suggest that because we can't tell for sure, we should wait and see.
In truth, nobody knows for sure quite how much the temperature will rise, but rise it will. Inaction or complacency heightens risk, gambling with the entire ecology of the planet, and the welfare of everyone on it.
This post is the Basic version (written by Graham Wayne) of the skeptic argument "Climate sensitivity is low". For the stout of heart, be sure to also check out theAdvanced Version by Dana which is currently getting rave reviews on Climate Progress.
Posted by gpwayne at 14:19 PM
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Comments 1 to 7:
1. huntjanin at 16:05 PM on 21 September, 2010Good post but in my opinion it needs a last sentence, along the lines of "remedial measures should therefore be adopted befor it is too late."
2. MattJ at 16:31 PM on 21 September, 2010I thought the last sentence was already pretty good. It really doesn't need the "before it is too late" kind of thing huntjanin proposes.
In fact, I was pretty pleased with the way it built up carefully to the pivotal and climactic statements, "Even such a small rise would signal many damaging and highly disruptive changes to the environment. In this light, the arguments against mitigation because of climate sensitivity are a form of gambling."
That is the essential point of the post: it is a form of gambling, and a particularly foolish one, like that game 'chicken' middle schoolers play -- but on a planetary scale.
In fact, if I were to ask to any change at all, it would be right here, rather than at the end: something to make it clear that we are not talking about just any 'gambling', but such a particularly reckless one, one where the odds are not only heavily against us, but the price paid is unimaginably high compared to any other form of gambling.
So I might, for example, change "a form of gambling" to "the worst sort of gamble, with planetary disaster for the price of losing."
3. Bern at 17:14 PM on 21 September, 2010I thought the entire article was well written, Graham, thanks.
Regarding the above comments on gambling, and stressing the potential disastrous outcomes - I guess it's a fine line to be walked, between over-caution on the one hand, which may lead to complacency, and alarmism on the other, which will of course lead to dismissal by the denialosphere. (Mind you, the skeptic tendency to leave zero space between 'alarmism' and 'nothing to worry about' makes that a particularly difficult task...)
If the more pessimistic results from the climate models are at all correct, it's not just gambling - it's more like playing russian roulette, but with nuclear weapons... if you're wrong, it doesn't just affect you, it affects everyone else as well. Sure, it may just be a sub-kiloton tactical nuke, that 'only' takes out your neighbourhood. Then again, it might be the launch code for the world's entire arsenal.The sad bit is that some people look at that problem, and see that it might not be their neighbourhood, but, say, a neighbourhood in Bangladesh, or a low-lying island nation, and they think "Meh, it doesn't affect me" and push the button anyway...
4. Riccardo at 17:46 PM on 21 September, 2010Apart from the die-hard skeptics, I think that for the general public is not even a gambling. My impression is that our time horizon is pretty near, we're not able (or not willing) to consider long term plans. In this sense we are culturally limited to the financial-style next quarter results.These considerations does not apply just to climate or global resources limitation but even to our everyday life. And it's the prologue for the disaster.
5. adelady at 18:21 PM on 21 September, 2010Riccardo "My impression is that our time horizon is pretty near, we're not able (or not willing) to consider long term plans."
I really think it's a failure of the imagination. I can speculate about my grandchildren's grandchildren. When people talk about this they don't really visualise it, they just hope that they'll be decent people who'll enjoy life in much the same way we do.
In this I'm more with Hansen. I see good possibilities if this generation and the next does the right thing. I see nasty stuff if we and they don't. Of course for them, it'll be just the way the world is.
But my generation is not too thrilled about the way our predecessors mucked up our forests and agricultural lands and introduced pests of every kind. I'd hope that our descendants will see that we did our best even though it was too little too late for some things they'll never get to see.
6. Michael Le Page at 20:16 PM on 21 September, 2010A few little things that struck me:
It seems a little odd to include Royer 2007 in the climate model category, it's a bit of a hybrid but based on past changes in CO2.
Also, where does that the top limit for Royer come from? The paper states "GEOCARBSULF simulations cannot exclude the possibility of a high climate sensitivity"?
Finally, why not include Lunt 2010 and Pagani 2010?
7. Riccardo at 01:20 AM on 22 September, 2010adelady,maybe i looked pessimistic while i'm not. What I've tryed to say is that it's a broader cultural problem and consequently broader changes in our societies are required. In this, science alone is not enough.
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A detailed look at Hansen's 1988 projectionsHansen et al. (1988) used a global climate model to simulate the impact of variations in atmospheric greenhouse gases and aerosols on the global climate. Unable to predict future human greenhouse gas emissions or model every single possibility, Hansen chose 3 scenarios to model. Scenario A assumed continued exponential greenhouse gas growth. Scenario B assumed a reduced linear rate of growth, and Scenario C assumed a rapid decline in greenhouse gas emissions around the year 2000.
Misrepresentations of Hansen's Projections
The 'Hansen was wrong' myth originated from testimony by scientist Pat Michaels before US House of Representatives in which he claimed "Ground-based temperatures from the IPCC show a rise of 0.11°C, or more than four times less than Hansen predicted....The forecast made in 1988 was an astounding failure."
This is an astonishingly false statement to make, particularly before the US Congress. It was also reproduced in Michael Crichton's science fiction novel State of Fear, which featured a scientist claiming that Hansen's 1988 projections were "overestimated by 300 percent."
Compare the figure Michaels produced to make this claim (Figure 1) to the corresponding figure taken directly out of Hansen's 1988 study (Figure 2).
Figure 1: Pat Michaels' presentation of Hansen's projections before US Congress
Figure 2: Projected global surface air temperature changes in Scenarios A, B, and C (Hansen 1988)
Notice that Michaels erased Hansen's Scenarios B and C despite the fact that as discussed above, Scenario A assumed continued exponential greenhouse gas growth, which did not occur. In other words, to support the claim that Hansen's projections were "an astounding failure," Michaels only showed the projection which was based on the emissions scenario which was furthest from reality.
Gavin Schmidt provides a comparison between all three scenarios and actual global surface temperature changes in Figure 3.
Figure 3: Hansen's projected vs. observed global temperature changes (Schmidt 2009)
As you can see, Hansen's projections showed slightly more warming than reality, but clearly they were neither off by a factor of 4, nor were they "an astounding failure" by any reasonably honest assessment. Yet a common reaction to Hansen's 1988 projections is "he overestimated the rate of warming, therefore Hansen was wrong." In fact, when skeptical climate scientist John Christy blogged about Hansen's 1988 study, his entire conclusion was "The result suggests the old NASA GCM was considerably more sensitive to GHGs than is the real atmosphere." Christy didn't even bother to examine why the global climate model was too sensitive or what that tells us. If the model was too sensitive, then what was its climate sensitivity?
This is obviously an oversimplified conclusion, and it's important to examine why Hansen's projections didn't match up with the actual surface temperature change. That's what we'll do here.
Hansen's AssumptionsGreenhouse Gas Changes and Radiative Forcing
Hansen's Scenario B has been the closest to the actual greenhouse gas emissions changes. Scenario B assumes that the rate of increasing atmospheric CO2 and methane increase by 1.5% per year in the 1980s, 1% per year in the 1990s, 0.5% per year in the 2000s, and flattens out (at a 1.9 ppmv per year increase for CO2) in the 2010s. The rate of increase of CCl3F and CCl2F2 increase by 3% in the '80s, 2% in the '90s, 1% in the '00s, and flatten out in the 2010s.
Gavin Schmidt helpfully provides the annual atmospheric concentration of these and other compounds in Hansen's Scenarios. The projected concentrations in 1984 and 2010 in Scenario B (in parts per million or billion by volume [ppmv and ppbv]) are shown in Table 1.
Table 1: Scenario B greenhouse gas (GHG) concentration in 1984, as projected by Hansen's Scenario B in 2010, and actual concentration in 2010
GHG 1984 Scen. B 2010 Actual 2010
CO2 344 ppmv 389 ppmv 392 ppmv
N2O 304 ppbv 329 ppbv 323 ppbv
CH4 1750 ppbv 2220 ppbv 1788 ppbv
CCl3F 0.22 ppbv 0.54 ppbv 0.24 ppbv
CCl2F2 .038 ppbv 0.94 ppbv 0.54 ppbv
We can then calculate the radiative forcings for these greenhouse gas concentration changes, based on the formulas from Myhre et al. (1998).
Total Scenario B greenhouse gas radiative forcing from 1984 to 2010 = 1.1 W/m2
The actual greenhouse gas forcing from 1984 to 2010 was approximately 1.06 W/m2 (NASA GISS). Thus the greenhouse gas radiative forcing in Scenario B was too high by about 5%.
Climate Sensitivity
Climate sensitivity describes how sensitive the global climate is to a change in the amount of energy reaching the Earth's surface and lower atmosphere (a.k.a. a radiative forcing). Hansen's climate model had a global mean surface air equilibrium sensitivity of 4.2°C warming for a doubling of atmospheric CO2 [2xCO2]. The relationship between a change in global surface temperature (dT), climate sensitivity (λ), and radiative forcing (dF), is
dT = λ*dF
Knowing that the actual radiative forcing was slightly lower than Hansen's Scenario B, and knowing the subsequent global surface temperature change, we can estimate what the actual climate sensitivity value would have to be for Hansen's climate model to accurately project the average temperature change.
Actual Climate Sensitivity
One tricky aspect of Hansen's study is that he references "global surface air temperature." The question is, which is a better estimate for this; the met station index (which does not cover a lot of the oceans), or the land-ocean index (which uses satellite ocean temperature changes in addition to the met stations)? According to NASA GISS, the former shows a 0.19°C per decade global warming trend, while the latter shows a 0.21°C per decade warming trend. Hansen et al. (2006) – which evaluates Hansen 1988 – uses both and suggests the true answer lies in between. So we'll assume that the global surface air temperature trend since 1984 has been one of 0.20°C per decade warming.
Given that the Scenario B radiative forcing was too high by about 5% and its projected surface air warming rate was 0.26°C per decade, we can then make a rough estimate regarding what its climate sensitivity for 2xCO2 should have been:
In other words, the reason Hansen's global temperature projections were too high was primarily because his climate model had a climate sensitivity that was too high. Had the sensitivity been 3.4°C for a 2xCO2, and had Hansen decreased the radiative forcing in Scenario B slightly, he would have correctly projected the ensuing global surface air temperature increase.
The argument "Hansen's projections were too high" is thus not an argument against anthropogenic global warming or the accuracy of climate models, but rather an argument against climate sensitivity being as high as 4.2°C for 2xCO2, but it's also an argument for climate sensitivity being around 3.4°C for 2xCO2. This is within the range of climate sensitivity values in the IPCC report, and is even a bit above the widely accepted value of 3°C for 2xCO2.
Spatial Distribution of Warming
Hansen's study also produced a map of the projected spatial distribution of the surface air temperature change in Scenario B for the 1980s, 1990s, and 2010s. Although the decade of the
2010s has just begun, we can compare recent global temperature maps to Hansen's maps to evaluate their accuracy.
Although the actual amount of warming (Figure 5) has been less than projected in Scenario B (Figure 4), this is due to the fact that as discussed above, we're not yet in the decade of the 2010s (which will almost certainly be warmer than the 2000s), and Hansen's climate model projected a higher rate of warming due to a high climate sensitivity. However, as you can see, Hansen's model correctly projected amplified warming in the Arctic, as well as hot spots in northern and southern Africa, west Antarctica, more pronounced warming over the land masses of the northern hemisphere, etc. The spatial distribution of the warming is very close to his projections.
Figure 4: Scenario B decadal mean surface air temperature change map (Hansen 1988)
Figure 5: Global surface temperature anomaly in 2005-2009 as compared to 1951-1980 (NASA GISS)
Had Hansen used a climate model with a climate sensitivity of approximate 3.4°C for 2xCO2 (at least in the short-term, it's likely larger in the long-term due to slow-acting feedbacks), he would have projected the ensuing rate of global surface temperature change accurately. Not only that, but he projected the spatial distribution of the warming with a high level of accuracy. The take-home message should not be "Hansen was wrong therefore climate models and the anthropogenic global warming theory are wrong;" the correct conclusion is that Hansen's study is another piece of evidence that climate sensitivity is in the IPCC stated range of 2-4.5°C for 2xCO2.
This post is the Advanced version (written by dana1981) of the skeptic argument "Hansen's 1988 prediction was wrong". After reading this, I realised Dana's rebuttal was a lot better than my original rebuttal so I asked him to rewrite the Intermediate Version. And just for the sake of thoroughness, Dana went ahead and wrote a Basic Version also. Enjoy!
Posted by dana1981 at 11:38 AM
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Comments 1 to 50 out of 121:
1. krab at 14:15 PM on 20 September, 2010Misprint on the first line. Says 1998; should be 1988.
Response: Fixed, thanks
2. actually thoughtfull at 14:30 PM on 20 September, 2010It is hard to look at Hansen's 1988 work without seeing he got it right! A few quibbles, but the major mechanisms are all included, and he is off by a few tenths of a degree over 22 years! And the fix is very clear - he used 4.2 instead of 3 or 3.4 for climate sensitivity.
The takehome message is climate scientists have this dialed in. With 22 years more research, current models are that much better.
"Hansen got it wrong" is a lie - pure and simple.
3. paulm at 15:11 PM on 20 September, 2010Heres some interesting analysis...
The Twin GHGs ParadoxThe means by which a greenhouse gas (GHG) forces climate change is sometimes called radiative forcing.
Moderator Response: Please provide more context when you post a link.
4. krab at 15:12 PM on 20 September, 2010I wonder if you would consider typesetting the math with LaTeX? Would make it lots more readable. You could e.g. use http://www.codecogs.com/latex/eqneditor.php. Or if you already know LaTeX, just use TTH: http://hutchinson.belmont.ma.us/tth/
5. macwithoutfries at 15:40 PM on 20 September, 2010The other thing that I think should be pointed out is that Hansen scenario B was also taking into consideration a large volcanic eruption in 1995 while Pinatubo - which can be clearly seen in the actual data - was in 1991 - once you also correct for that the scenario B already looks identical to real measured values!
6. krab at 16:05 PM on 20 September, 2010@paulm: That website proves nothing. Radiative forcing F is a multivariate nonlinear function. But for small variations, we can Taylor-expand and to first order it is the sum of the first derivatives. The particular objection raised is that for example d^2F/d(CO2)/d(N2O) is not zero. I agree it's not. But its contribution to dF is much smaller than the linear part. As it's unknown, it contributes to the uncertainty (error-bar) in the calculation.
7. caerbannog at 16:52 PM on 20 September, 2010One thing that folks should keep in mind is that your typical el-cheapo Best-Buy/Walmart/whatever laptop has more computing horsepower than what Hansen had available to him to conduct his climate-modeling simulations back in 1988. This should put things in perspective here, and also give folks a fuller appreciation of Hansen's genius.
8. Sense Seeker at 20:26 PM on 20 September, 2010Something here does not make sense. Nowhere do you mention what the actual emissions WERE over the intervening period. You cannot simply compare one of Hansen's scenarios with what actually happened in terms of outcomes, if you do not take into account the inputs.
If the temperature curve nicely follows Hansen's scenario B, but the emissions increased exponentially (i.e., according to scenario A), Hansen's model was overestimating by a much larger margin.
9. Riccardo at 20:46 PM on 20 September, 2010Sense Seeker,you missed something. Two quotes from the post:
"Scenario A assumed continued exponential greenhouse gas growth, which did not occur."
"Hansen's Scenario B has been the closest to the actual greenhouse gas emissions changes."
10. Sense Seeker at 21:09 PM on 20 September, 2010Ricardo, you are mostly right but not completely. (Unless I missed something more, which is of course now a non-negligible option.)
Shouldn't Table 1 give the realised Greenhouse Gas (GHG) Concentration in 1984 and 2010, rather than the one from Scenario B? The calculations seem to be based on scenario B, not the realised emissions. The real ones may be most like scenario B compared to A or C, but are unlikely to be identical. If you only want to test the model, you need to use the observed emissions as input.
11. Tenney Naumer at 21:14 PM on 20 September, 2010Once the data for 2010 are used, his accuracy will have been prophetic.
12. Sense Seeker at 21:15 PM on 20 September, 2010And if you want to test Hansen's scenario B as a prediction, rather than the underlying model, you needn't bother with any calculation. You can just read if from the graph.
13. Sense Seeker at 21:22 PM on 20 September, 2010There is one more thing I don't understand. The calculations did not use Hansen's model, but a set of equations from a different source (Myhre et al 1998). Comparison with the forcings as established (beyond doubt, is seems) with an unexplained NASA method, and then conclude that Hansen's model was almost accurate...
I am sorry, I can see Hansen got it about right, but this posting adds little to my understanding.
14. Ken Lambert at 23:04 PM on 20 September, 2010I clicked the link to NASA-GISS for the +1.1W/sq.m 2010 relative to 1984 forcing here:
http://data.giss.nasa.gov/modelforce/RadF.txt
and found data only to 2003 and nothing like +1.1. Please explain the calculation?
My eyesight must be playing tricks for I see the actual temperatures running close or below Scenario C not Scenario B. Is that what you meant?
And what of the climate responses - where is the estimate of WV and Ice albedo feedback and radiative cooling feedback?
Seems like a contrived Hansen apologia with only half the story to me.
15. Riccardo at 23:27 PM on 20 September, 2010Sense Seeker,#10 in this post there's a comparison of Hansen's calculation in 1988 not a thorough comparison of model results. How could he know the actual emissions in the future? Someone else could do now some new calculations with actual emissions and best available model now, but this is a different story. A good idea for a new post ;)
#13 the model is not on radiative forcing alone, it's much more than this; it is called a General Circulation Model (GCM). Radiative forcings come from radiative tranfer codes that are pluged into the GCMs. I think you should dig a little bit more on GCMs; NASA GISS provide a lot ofinformations (and the code itself) that I'm sure you'll find intersting.
16. Riccardo at 23:37 PM on 20 September, 2010Ken Lambert,it's way too easy to talk about apologia without even bothering to look at the details on how things work. This attitude just highlight the unwillingness to learn the science but still dismissing it.The feedbacks are, indeed, feedback, not forcings. Why should they be listed in the same table as the forcings? The albedo, water vapour feedbacks and others are the results of the full calculations and are not parametrized.
17. Ken Lambert at 23:55 PM on 20 September, 2010Riccardo #16
Unfortunately the measures 'air surface temperature' and GISS and HADCRUT3 temperature anomalies are the result of ALL the forcings - both radiative and feedbacks.
Claiming that Hansen was out by only 5% on half the story when the feedbacks (particularly
WV and CO2 interaction) are the least understood is the missing part of this article.
So we are closest Scenario C with the temperature record??
18. Scrooge at 00:09 AM on 21 September, 2010First I want to say that to be able to come up with those projections in 1988 is remarkable. I think I was still using an Atari 800 at the time. Now this may be a stupid question but as discussed in a previous post, is the idea that we should be naturally cooling incorporated into the model. Of course I assume it is but just one of those nagging questions.
19. Riccardo at 00:19 AM on 21 September, 2010Ken Lambert,still confusing forcings and feebacks, do you?Anyway, Hansen calculation also are "the result of ALL the forcings - both radiative and feedbacks." (sic). And within 5%.
20. Riccardo at 00:23 AM on 21 September, 2010Scrooge,natural cooling is ignored in GCM. It happens on a time frame of millennia which usually is not considered.
21. Albatross at 01:19 AM on 21 September, 2010Wonder if Michaels is going to retract the misleading and erroneous testimony that he gave before US House of Representatives? I mean in the spirit of accountability,transparency and rigor that he demands of the IPCC?
Excellent job Dana. Am I correct in understanding that emission scenarios B and C were the same up until 2000?
22. angusmac at 01:22 AM on 21 September, 2010A close look at Figure 3 shows that temperatures are actually running below Scenario C - the zero-increase in CO2 from 2000.
This decline has not happened. Therefore, the only conclusion that can be made from present day temperature readings is that Hansen (1988 & 2006) got it wrong.
23. CBDunkerson at 02:04 AM on 21 September, 2010angusman #22, scenarios B and C and the actual temperature record are all very similar to each other through 2005. Since 2005 actual temperatures have been roughly in line with scenario C (below in some years, above in others). However, that is FAR too short a time frame on which to judge the validity of the model. If actual results continued tracking along scenario C for 15+ years then the model would be off significantly. If the warming being seen this year continued then we'd be back 'on track' closer to scenario B.
That said, Hansen's 'short term' climate sensitivity factor in 1988 was definitely too high and thus his results should be expected to go further off as time goes by.
Hansen 2006 essentially explained HOW the 1988 analysis got it wrong... so to say that 2006 is itself wrong... would seem to be arguing that Hansen 1988 was correct. :]
24. dana1981 at 02:54 AM on 21 September, 2010Sense Seeker - I didn't provide the actual atmospheric concentrations of the various GHGs, but I did provide the actual radiative forcing associated with them, which is what matters for these calculations.
Also Hansen '88 provided his formulas for dT but not dF, so I used Myhre for the dFs, which are reasonably close to Hansen's values.
Ken Lambert - as the GISS forcing link only provided data up to 2003, I extrapolated to 2010 to get a value of approximately 1.06 W/m2.
Several commenters have stated that the actual temperatures have run close to Scenario C, which completely misses the point, and I would suggest re-reading the rebuttal. Actual emissions have not been very similar to Scenario C, so comparing to Scenario C rather than B doesn't make sense.
Albatross - yes, Scenarios B and C were very similar (perhaps identical, I'd have to go back and look) up until 2000.
25. Sense Seeker at 08:30 AM on 21 September, 2010A night's sleep does help. I can see what you were trying to do.
You are comparing the inputs of Hansen's scenario B (translated into forcings) and the actual changes in the input variables (as 'observed' forcings), and then compare Hansen's output (= projected temperatures) with the real output (= realised temperatures). From that you conclude that Hansen's model was 24% too sensitive. It is a pity that the detour via forcings is there, but I guess that is the best way to summarise all different emissions? (I cannot judge that.) You could consider explaining why the translation into forcings is necessary and justified; it was not obvious to me when I first read it.
To guide the reader, you could also consider indicating somewhere in the beginning of your explanation what you are going to do, in broad terms. (Determine difference in input values (GHGs) and compare to differences in output (temp) between Hansen's model and reality.)
PS: typo "global surface temperature (dF)" should be (dT)?
26. Joe Blog at 08:49 AM on 21 September, 2010Youve lost me with this analysis... in the top graph, the closest is scenario C to observations... A and B appear to clearly over estimate climate sensitivity... Now B is the closest to observed emissions clearly, But C is the closest to observations, how can this mean anything other than an overstated climate sensitivity?
Now it dosnt matter one iota what anyone's opinion is on what the temps "will be" in a decade, all that matters for testing the model is a straight comparison between projected and observations.
It may be due
27. archiesteel at 09:01 AM on 21 September, 2010@Joe Blog: "how can this mean anything other than an overstated climate sensitivity"
Isn't that the conclusion of the article, i.e. that Hansen overestimated climate sensitiviy (4.2C instead of 3.4C)?
Yes, so Hansen was wrong, in his climate sensitivity. It certainly doesn't prove Hansens projections were accurate, or disprove criticisms of his projections, as the article claims to do.
29. Rob Honeycutt at 09:23 AM on 21 September, 2010Joe... You have to bear in mind this is coming from a study done in 1988 and it's an incredibly complex model. Given that Hansen managed to closely predict warming for the following 22 years is astounding. As well, give how much less was known at the time about climate sensitivity it's amazing that he settled on a number that is so close to reality.
The scenario C is actually not as close because (I believe) it used more optimistic GHG emissions rates that didn't come to pass. B has the right GHG emissions and is only off on climate sensitivity by 0.8C.
It's also impressive that his middle scenario is the closest. It's what you'd be aiming for in a study like this.
Think of it this way. What if you had to guess what global temperatures would be 22 years from now. How close could you get? This is essentially Hansen hitting the first ring outside the bulls eye from a very very very long distance.
30. dana1981 at 09:57 AM on 21 September, 2010archiesteel - you are correct. Joe Blog, you have missed the point entirely.
The point, once again, is that yes, Hansen's model's sensitivity of 4.2°C for 2xCO2 is too high (in the short-term), but it also tells us that 3.4°C for 2xCO2 is approximately right.
This sort of inability to see past the conclusion you want to see is exactly what I was talking about - "a common reaction to Hansen's 1988 projections is 'he overestimated the rate of warming, therefore Hansen was wrong'...This is obviously an oversimplified conclusion, and it's important to examine why Hansen's projections didn't match up with the actual surface temperature change. That's what we'll do here..."
31. dana1981 at 10:04 AM on 21 September, 2010Sense Seeker - you can't get to a surface temperature change from a GHG change without determining the associated forcing (and knowing the climate sensitivity parameter). I'm a big proponent of 'show your work', so I don't want to skip that step.
Personally I think the logical process in the advanced version is reasonably clear, but the intermediate and basic versions are less detailed for those who just want to get the general gist.
32. dana1981 at 10:22 AM on 21 September, 2010I did like your comment on adding the actual 2010 GHG concentrations to Table 1, Sense Seeker, and have updated the post accordingly.
33. John Chapman at 14:43 PM on 21 September, 2010A slightly pedantic point ... in the calculation the input figures are 3 or 4 significnat figures. Please make them two. eg. 389 ppm -> 390, 329 -> 330, 1788 -> 1800. The rounding will not affect the final 2 sig fig result.
The earth only warmed 31 % as much as predicted. This is less than scenario “C” which is what was predicted for what would happen with stringent carbon cuts.
When the “debate is over” you have all of the answers and are expected to be correct.If he got climate sensitivity wrong that is just an excuse, this means his predictions of 2020 and beyond will be way off track and getting worse each decade.
35. CBDunkerson at 21:52 PM on 21 September, 2010NETDR, there are a couple of glaring flaws in your analysis;
"From 1988 to present [Aug 2010] the warming has been .53 ° C - .31 ° C = .22 ° C"
0.53 C is the anomaly for JUST August 2010 while 0.31 C is the anomaly for the entire year 1988. Monthly variations are, of course, greater than annual variations. This method is also subject to huge variations depending on the precise timing. If we pick different months, say March 2010 with 0.84 C anomaly minus November 1988 with -0.03 C anomaly we get a +0.87 C increase... MORE than the model predicted.
Also, LOOK at the Hansen graph in the URL you posted. The temperature values BEFORE 1988 diverge significantly from the actual temperature record in individual years. For instance, for 1981 scenario B 'predicted' (7 years after the fact) that the anomaly had been roughly double what the actual record showed. From this we can conclude either that Hansen's model was wrong before it was even released... OR we could be remotely logical and realize that these models were never intended to precisely match each and every year... which is the test you are applying. A model is 'accurate' if it matches the long term trend. Picking out individual years (or months) and saying 'the model is off by X% at this moment in time' is meaningless.
Through 2005 the model trend lined up with scenarios B & C. Since 2005 it has lined up with scenario C while emissions have actually been just a bit below those assumed for scenario B. Thus, it could be said that the trend isn't matching the model's prediction for our approximate emissions over the past five years... except that is a ridiculously short period of time on which to base a trend.
36. NETDR at 00:15 AM on 22 September, 2010CB Dunkerson [35]
If you notice all scenarios start approximately together in 1988. They can’t possibly exactly predict the past exactly without cheating. They were adjusted to converge on the right answer in 1988. [No problem, I would do it that way too.]
You complained that the time period I chose for my end point was too short. Let’s go back to 2009 and use a 5 year average.
The 5 year average for 1988 was .25 ° C [Anomaly]The 5 year average for 2009 was .54° CThe 5 year average for Hansen’s prediction is hard to get precisely but it seems to be .9 ° Chttp://data.giss.nasa.gov/gistemp/graphs/Fig.A2.txt
Let’s do the math.
The chart predicts .9 ° C - .25 ° C = .65Reality is .54 - .25 = .29
Even with uncorrected UHI and other surface station issues.
If I had used Satellite data his predictions look worse, because there are no perking lots in space.
In my book that is pretty poor performance.
His excuses ring hollow to me, it is like the horse player who bets on the wrong horse but shows how he could have picked the right one if only. Everyone “could have” and “should have “. Putting those guesses to work on predicting the future will verify or refute them. Anyone can predict the past.
37. Baz at 00:25 AM on 22 September, 2010Can someone help me out here? I can't see (by eyeballing) that the actual temps match any of them, even C. However, that's not important to me. Can someone please explain why the graph shows HadCRUt3 (in pink) dipping well into the 0.5s when the data says it hasn't.http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txtI know there is obviously a simple explanation! Thanks.
38. Daniel Bailey at 00:42 AM on 22 September, 2010Re: Baz (37)
"Can someone please explain why the graph shows HadCRUt3 (in pink) dipping well into the 0.5s when the data says it hasn't."
You can try asking Phil Jones. :)
The Yooper
39. doug_bostrom at 00:58 AM on 22 September, 2010...like the horse player who bets on the wrong horse but shows how he could have picked the right one if only.
Or one can take the approach of imagining much of the field had never raced, thus concluding one's own pick won. Alternatively, how about ignoring most available data in order to gin up a comfy conclusion?
40. CBDunkerson at 01:29 AM on 22 September, 2010NETDR #36 writes;
"They can’t possibly exactly predict the past exactly without cheating."
Yet your prior post objected to their 'failure' to exactly predict the future... down to the month.
"The 5 year average for 2009 was .54° C"
Actually, 0.55 C based on the URL you provided. Apparently you rounded down.
"The 5 year average for Hansen’s prediction is hard to get precisely but it seems to be .9 ° C"
Yes, since all of the values from 2005 through 2009 on scenario B are clearly less than 0.9 C (the only one which comes close is 2009) it definitely IS hard to get how you come up with that average.
The 'UHI skews temperature records' and 'satellite temperatures are different' bits have been debunked on this site so many times that I can't be bothered.
41. dana1981 at 02:02 AM on 22 September, 2010I have to say, it's a little irritating how many people can't get past the "it looks like Scenario C" perception. Is the entire rebuttal over their heads? Are they just incapable of seeing anything other than what they want to see?
42. Baz at 02:10 AM on 22 September, 2010Thanks Daniel, but after the Email Episode he stopped replying to my emails!
37. Seriously, anyone? Please excuse my ignorance.
43. CBDunkerson at 02:36 AM on 22 September, 2010dana1981 #41: Are you assuming they actually READ the whole article? It seems pretty clear to me that several of those posting objections have not.
Baz #37: I'm not sure which graph you are referring to, but I'd guess the problem is different baseline periods. If the anomaly numbers you are looking at were computed against a different baseline then the graph then you're going to get different values. The relative values should be the same, but the absolute numbers would be shifted by whatever the difference between the baselines is.
44. Joe Blog at 02:55 AM on 22 September, 2010dana1981 at 02:02 AM
No dana, saying if we change his models assumptions to thus, does not actually make it right, or more accurate... this isnt a rebuttal, but a postmortem. Saying why something is dead dosnt change the fact it is dead.
C is the closest scenario to observations in temp, B is the closest in relation to emissions. Now obviously, some of the criticisms cited are pushing the envelope, in how they have chosen to interpret the predictions vrs temp... but so is this one. So what percentage of the temperature anomaly is B from observations? This is relevant.
Im not drawing any other conclusion from this, other than Hansen had it wrong in 88. Because he did, you have demonstrated it, it is obvious from a glance at the predictions vrs
observations. This dosnt change anything. I still think we are effecting climate through co2 emissions... But Hansen had assumed a higher climate sensitivity than observations. And you have demonstrated this, But then you are claiming it as a rebuttal to criticisms, that have made the exact same observation???? (John Christy)
45. Badgersouth at 03:13 AM on 22 September, 2010@Dana1981 & John Cook:
Because it is a poor B&W copy of a color graphic, Figure 2 is virtually worthless to anyone not already familiar with its contents. Suggest that someone track down a color version of this graphic and replace the B&W with it.
Although Figure 3 is a color graphic, the colors chosen are pretty much shades of the same basic color. Is it possible to use a different set of colors in this graphic?
46. Albatross at 03:30 AM on 22 September, 2010Christy said:
"The result suggests the old NASA GCM was considerably more sensitive to GHGs than is the real atmosphere."
Schmidt and Dana showed this to be a gross exaggeration. Climate Sensitivity (CS) in Hansen's early model was too high (4.2 C versus 3.4 C), but not "considerably" too high, especially in the context of the range of uncertainty in CS of +1.5 to +4.5 C presented in the IPCC's AR4.
Michaels said:
"Ground-based temperatures from the IPCC show a rise of 0.11°C, or more than four times less than Hansen predicted....The forecast made in 1988 was an astounding failure."
Schmidt has shown that statement to be patently false. Observed rate of warming between 1984 (year simulation started) and 2009 = +0.19 C per decade. Predicted rate of warming over same period (with GHG emissions being too high and with too high a climate sensitivity in the model) = +0.26 C.
And is that is not good enough, the error bars of the observations and predictions data overlap by quite a bit.
Also, I agree with CBDunkerson's assessment @43.
What I also found odd is that, to my knowledge, neither Michaels nor Christy have made the effort to make their own predictions concerning the expected rate of warming 20-30 years form now.
47. Badgersouth at 03:39 AM on 22 September, 2010As best I can tell from reading the literature, climate models have very short shelf lives. How many models have Dr. Hansen and his team developed since 1998? I presume that each succeeding model was an improvement over its predecessor.
I suggest that everyone's time and energy would better be spent on focusing on the validity of the forecasts being made today by current crop of climate models than constantly
revisiting no longer relevant forecasts made in 1998 by a single model that is no longer in use.
48. NETDR at 03:43 AM on 22 September, 2010CB Dunkerson
The Pat Michaels analysis is a straw-man defense. Dr Hansen's model was seriously wrong but not as seriously as Pat said. So what?
Who said anything about being able to predict the future or past down to the month ? He ran the models and back-cast to obtain the best possible fit. . Of course each squiggle of the temperature chart is not matched exactly. That is way beyond our capability at this time.
His prediction
Despite your quibbles he was seriously wrong !
The chart predicts .9 ° C - .25 ° C = .6° C 5 Reality is .54 - .25 = .29 ° C
This is using a 5 year average not a month by month value. His model points straight up for 2010 so the model will look worse next year.
There was 44 % as much warming as predicted. [+, - quibbles]
So if the .29 ° C rate for 30 years is continued for 100 years you get about 1 ° C warming which is the value for CO2 alone with no feedback. For this we are seriously discussing tens of trillions of dollars of taxes and cap and trade ?
Joe said it right : “This isn’t a rebuttal it is a postmortem” I wasn’t particularly interested in the excuses why Dr Hansen was wrong. When you know all of the answers and the “debate is over” you have to be right ! No excuses allowed.
Any gambler can tell you why he was wrong !
So this article has proven he was wrong [in 88] and claimed it was a rebuttal to those that claim he was wrong. [in 88] Am I missing something ???
49. Albatross at 03:50 AM on 22 September, 2010NETDR @48,
You ask "Am I missing something ???"
Yes you are, very much so. But I am afraid that I do not have the patience right now. Maybe someone else feels more inclined.
50. Joe Blog at 03:55 AM on 22 September, 2010Albatross at 03:30
I would consider 23% more sensitive substantial, i suppose it comes down to how exactly
you want to measure it... if we go to absolute temperatures, we can claim basically absolute accuracy. But the Q is, did Hansen 88 accurately model climate since its hindcast... the answer is no.
There are actually other possibilities why the discrepancies, he may have climate sensitivity right, but other unrelated factors have thrown it off, say decreased UV effecting ozone, effecting stratospheric temps, effecting tropospheric pressure systems (or co2 doing the same) etc... Or did he assume a solar constant, and the reduced TSI is effecting it? the list goes on.
There is a bit o seeing what yah want to see going on here... Why i dont know, i agree with Dana that this has nothing to do with proving AGW wrong. Its just showing how the quantification's can become more confined with a greater data record. No surprises there. But how exactly this classes as an exoneration is quite frankly escaping me.
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A detailed look at Hansen's 1988 projectionsHansen et al. (1988) used a global climate model to simulate the impact of variations in atmospheric greenhouse gases and aerosols on the global climate. Unable to predict future human greenhouse gas emissions or model every single possibility, Hansen chose 3 scenarios to model. Scenario A assumed continued exponential greenhouse gas growth. Scenario B assumed a reduced linear rate of growth, and Scenario C assumed a rapid decline in greenhouse gas emissions around the year 2000.
Misrepresentations of Hansen's Projections
The 'Hansen was wrong' myth originated from testimony by scientist Pat Michaels before US House of Representatives in which he claimed "Ground-based temperatures from the IPCC show a rise of 0.11°C, or more than four times less than Hansen predicted....The forecast made in 1988 was an astounding failure."
This is an astonishingly false statement to make, particularly before the US Congress. It was also reproduced in Michael Crichton's science fiction novel State of Fear, which featured a scientist claiming that Hansen's 1988 projections were "overestimated by 300 percent."
Compare the figure Michaels produced to make this claim (Figure 1) to the corresponding figure taken directly out of Hansen's 1988 study (Figure 2).
Figure 1: Pat Michaels' presentation of Hansen's projections before US Congress
Figure 2: Projected global surface air temperature changes in Scenarios A, B, and C (Hansen 1988)
Notice that Michaels erased Hansen's Scenarios B and C despite the fact that as discussed above, Scenario A assumed continued exponential greenhouse gas growth, which did not occur. In other words, to support the claim that Hansen's projections were "an astounding failure," Michaels only showed the projection which was based on the emissions scenario which was furthest from reality.
Gavin Schmidt provides a comparison between all three scenarios and actual global surface temperature changes in Figure 3.
Figure 3: Hansen's projected vs. observed global temperature changes (Schmidt 2009)
As you can see, Hansen's projections showed slightly more warming than reality, but clearly they were neither off by a factor of 4, nor were they "an astounding failure" by any reasonably honest assessment. Yet a common reaction to Hansen's 1988 projections is "he overestimated the rate of warming, therefore Hansen was wrong." In fact, when skeptical climate scientist John Christy blogged about Hansen's 1988 study, his entire conclusion was "The result suggests the old NASA GCM was considerably more sensitive to GHGs than is the real atmosphere." Christy didn't even bother to examine why the global climate model was too sensitive or what that tells us. If the model was too sensitive, then what was its climate sensitivity?
This is obviously an oversimplified conclusion, and it's important to examine why Hansen's projections didn't match up with the actual surface temperature change. That's what we'll do here.
Hansen's AssumptionsGreenhouse Gas Changes and Radiative Forcing
Hansen's Scenario B has been the closest to the actual greenhouse gas emissions changes. Scenario B assumes that the rate of increasing atmospheric CO2 and methane increase by 1.5% per year in the 1980s, 1% per year in the 1990s, 0.5% per year in the 2000s, and flattens out (at a 1.9 ppmv per year increase for CO2) in the 2010s. The rate of increase of CCl3F and CCl2F2 increase by 3% in the '80s, 2% in the '90s, 1% in the '00s, and flatten out in the 2010s.
Gavin Schmidt helpfully provides the annual atmospheric concentration of these and other compounds in Hansen's Scenarios. The projected concentrations in 1984 and 2010 in Scenario B (in parts per million or billion by volume [ppmv and ppbv]) are shown in Table 1.
Total Scenario B greenhouse gas radiative forcing from 1984 to 2010 = 1.1 W/m2
The actual greenhouse gas forcing from 1984 to 2010 was approximately 1.06 W/m2 (NASA GISS). Thus the greenhouse gas radiative forcing in Scenario B was too high by about 5%.
Climate Sensitivity
Climate sensitivity describes how sensitive the global climate is to a change in the amount of energy reaching the Earth's surface and lower atmosphere (a.k.a. a radiative forcing). Hansen's climate model had a global mean surface air equilibrium sensitivity of 4.2°C warming for a doubling of atmospheric CO2 [2xCO2]. The relationship between a change in global surface temperature (dT), climate sensitivity (λ), and radiative forcing (dF), is
dT = λ*dF
Knowing that the actual radiative forcing was slightly lower than Hansen's Scenario B, and knowing the subsequent global surface temperature change, we can estimate what the actual climate sensitivity value would have to be for Hansen's climate model to accurately project the average temperature change.
One tricky aspect of Hansen's study is that he references "global surface air temperature." The question is, which is a better estimate for this; the met station index (which does not cover a lot of the oceans), or the land-ocean index (which uses satellite ocean temperature changes in addition to the met stations)? According to NASA GISS, the former shows a 0.19°C per decade global warming trend, while the latter shows a 0.21°C per decade warming trend. Hansen et al. (2006) – which evaluates Hansen 1988 – uses both and suggests the true answer lies in between. So we'll assume that the global surface air temperature trend since 1984 has been one of 0.20°C per decade warming.
Given that the Scenario B radiative forcing was too high by about 5% and its projected surface air warming rate was 0.26°C per decade, we can then make a rough estimate regarding what its climate sensitivity for 2xCO2 should have been:
In other words, the reason Hansen's global temperature projections were too high was primarily because his climate model had a climate sensitivity that was too high. Had the sensitivity been 3.4°C for a 2xCO2, and had Hansen decreased the radiative forcing in Scenario B slightly, he would have correctly projected the ensuing global surface air temperature increase.
The argument "Hansen's projections were too high" is thus not an argument against anthropogenic global warming or the accuracy of climate models, but rather an argument against climate sensitivity being as high as 4.2°C for 2xCO2, but it's also an argument for climate sensitivity being around 3.4°C for 2xCO2. This is within the range of climate sensitivity values in the IPCC report, and is even a bit above the widely accepted value of 3°C for 2xCO2.
Spatial Distribution of Warming
Hansen's study also produced a map of the projected spatial distribution of the surface air temperature change in Scenario B for the 1980s, 1990s, and 2010s. Although the decade of the 2010s has just begun, we can compare recent global temperature maps to Hansen's maps to evaluate their accuracy.
Although the actual amount of warming (Figure 5) has been less than projected in Scenario B (Figure 4), this is due to the fact that as discussed above, we're not yet in the decade of the 2010s (which will almost certainly be warmer than the 2000s), and Hansen's climate model projected a higher rate of warming due to a high climate sensitivity. However, as you can see, Hansen's model correctly projected amplified warming in the Arctic, as well as hot spots in northern and southern Africa, west Antarctica, more pronounced warming over the land masses of the northern hemisphere, etc. The spatial distribution of the warming is very close to his projections.
Figure 4: Scenario B decadal mean surface air temperature change map (Hansen 1988)
Figure 5: Global surface temperature anomaly in 2005-2009 as compared to 1951-1980 (NASA GISS)
Hansen's Accuracy
Had Hansen used a climate model with a climate sensitivity of approximate 3.4°C for 2xCO2 (at least in the short-term, it's likely larger in the long-term due to slow-acting feedbacks), he would have projected the ensuing rate of global surface temperature change accurately. Not only that, but he projected the spatial distribution of the warming with a high level of accuracy. The take-home message should not be "Hansen was wrong therefore climate models and the anthropogenic global warming theory are wrong;" the correct conclusion is that Hansen's study is another piece of evidence that climate sensitivity is in the IPCC stated range of 2-4.5°C for 2xCO2.
This post is the Advanced version (written by dana1981) of the skeptic argument "Hansen's 1988 prediction was wrong". After reading this, I realised Dana's rebuttal was a lot better than my original rebuttal so I asked him to rewrite the Intermediate Version. And just for the sake of thoroughness, Dana went ahead and wrote a Basic Version also. Enjoy!
Posted by dana1981 at 11:38 AM
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Comments 51 to 100 out of 121:
51. Albatross at 04:14 AM on 22 September, 2010Joe,
Dana is addressing misleading statement made by Michaels and Christy-- I have also addressed that in my post @46. Regardless, what you might consider or think is "substantial" is not necessarily indicative of what the reality is. The range given by IPCC for CS is 1.5 through 4.5 C. Hansen's original model had a CS was clearly on the high end of that range, I for one am not trying to ignore that. What I take issue is with certain people spinning that. Can I assume that you agree with what Michaels and Christy have said on this?
Science advances, Hansen had the intellect, know how and guts to make a bold prediction, that all things considered, was in good agreement with what actually transpired (predicted warming of 0.26 C per decade versus observed warming almost 0.20 C per decade).
I doubt that you, or I, or Michaels would venture to make such a prediction and get it even remotely correct.
Anyhow, that is the nature of science. You give it you best shot, using the best tools and information at your disposal now, and then someone else comes along and improves upon your technique, or down the road you improve upon your initial work. Hansen's seminal work has served as a building block for others.
52. angusmac at 04:18 AM on 22 September, 2010#43 Albatross, you are correct that Pat Michaels misled Senate but so has Dana1981 in this post.
The NASA GISS data up to August 2010 are shown in Figure 1. They are compared with Scenarios A, B and C in Hansen (2006). The blue line denotes the Land-Ocean Temperature Index (LOTI).
Figure 1: Scenarios A, B and C Compared with Measured NASA GISS LOTI (after Hansen, 2006)
I have used the LOTI data in Figure 1 because the GISS website states that this provides the most relaistic representation of global meam trends.
It is evident from Figure 1 that the best fit for actual temperature measurements is currently the emissions-held-at-year-2000-level Scenario C. Therefore it is incorrect for Dana1981 to contend that temperaturea are currently following a trajectory slightly below Scenarion B.
Nevertheless, I do agree #23 CBDunkerson that the time period is still relatively short for comparing the scenarios. Consequently I agree withHansen (2006) that we should wait until 2015 for distinction between the scenarios and useful comparison with the real world.
53. Albatross at 04:45 AM on 22 September, 2010Angusmac,
Nice graph. You use your Fig. 1 (which is what I assume to be an accurate replication of Fig. 2 in Hansen et al. (2006)) to make the assetion that:
"It is evident from Figure 1 [after Hansen. 2006] that the best fit for actual temperature measurements is currently the emissions-held-at-year-2000-level Scenario C".
Let us have a look at Hansen et al. (2006). They state that:
"Modeled 1988–2005 temperature changes are 0.59, 0.33, and0.40°C, respectively, for scenarios A, B, and C. Observed temperature change is 0.32°C and 0.36°C for the land–ocean index and meteorological station analyses, respectively.Warming rates in the model are 0.35, 0.19, and 0.24°C per decade for scenarios A, B. and C, and 0.19 and 0.21°C per decade for the observational analyses."
Now either Hansen et al. made a mistake and inadvertently swapped the warming rates for scenario B and C, or your claim (cited above) which is based on your Figure 1 is false. Because the warming rate for scenario B of +0.19 C is the same as the observed rate of warming in the LOTI data. You state that
Now there is an important caveat here of course, the data in Hansen et al. (2006) are for a different time window considered by Schmidt (2009). I do agree that it would be helpful if the predicted rate of warming for 1984-2009 for Scenario C could be included in Fig. 3 in the post.
It is evident that the time windows chosen to validate the projections yield different answers. But, even so, the claims made by Crichton and others are incorrect and misleading.
Hansen et al. (2006) also conclude that:
"Nevertheless, it is apparent that the first transient climate simulations (12) proved to be quite accurate, certainly not ‘‘wrong by 300%’’ (14)"
54. archiesteel at 06:29 AM on 22 September, 2010@NETDR: "The Pat Michaels analysis is a straw-man defense."
I'm not sure you know what a strawman argument is. What Albatross (not CBD) said certainly wasn't a strawman; for that, he would have had to ascribe to you an opinion that wasn't yours.
"Dr Hansen's model was seriously wrong but not as seriously as Pat said. So what?"
There is such a thing as "a little wrong", "seriously wrong" and "completely wrong" in science. You seem to believe that it's a binary condition, i.e. one is either wrong or right. Unfortunately, reality doesn't like such absolutes.
"For this we are seriously discussing tens of trillions of dollars of taxes and cap and trade ?"
Careful, your bias is showing.
An important fact for you to consider: if you agree with the analysis that shows Hansen was off on climate sensitivity by 0.8C for his choice of a 4.2C value, this means you *do* agree with a figure of about 3.4C for climate sensitivity.
Let me put it another way: either you agree that climate sensitivity is about 3.4C, or you don't believe this critique of Hansen 1988 is accurate, and thus can't use it this particular evidence to support your affirmation that Hansen got it wrong.
So, before we go any further, do you agree with the 3.4 figure for climate sensitivity?
"So this article has proven he was wrong [in 88] and claimed it was a rebuttal to those that claim he was wrong. [in 88] Am I missing something ???"
Yes, you are, but your use of multiple interrogation point and apparent obsession for boolean certainty in science make me wary of continuing this dialogue.
@Joe Blog: "But the Q is, did Hansen 88 accurately model climate since its hindcast... the answer is no."
Another, equally valid answer, would be that he answered it more accurately than others at the time. It's important to note that Hansen later acknowledged the differences, as this article does. The topic here is how contrarians have used the inaccuracy as an excuse to grossly underestimate climate sensitivity. That's the whole point of the article, unless I'm mistaken.
55. archiesteel at 06:36 AM on 22 September, 2010@Angusmap: "It is evident from Figure 1 that the best fit for actual temperature measurements is currently the emissions-held-at-year-2000-level Scenario C. Therefore it is incorrect for Dana1981 to contend that temperaturea are currently following a trajectory slightly below Scenarion B."
As I understand it, the question is not whether the actual record is closer to B or C, because we know real-world emissions are closer to emmission scenario B. Thus accuracy of the model has to be gauged in relation to scenario B.
Had emmissions been closer to C, then we'd be comparing the record with C, and would find Hansen 1998 had been amazingly accurate! :-)
Am I getting this right?
56. Albatross at 06:45 AM on 22 September, 2010Archiesteel @55,
You just stated what I was thinking of saying, but more eloquently and succinctly than I am capable of.
Earlier I suggested including the rate of warming for the 1984-2009 window for Scenario C, but in retrospect it is pointless comparing observations with Scenario C much beyond 2000 b/c the emissions (i.e., GHG forcing) for Scenario C after 2000 are not realistic. I suspect that is the reason why Schmidt and Dana did not include it in their analyses which extend almost a decade beyond 2000.
Hansen et al. included Scenario C in their validation up until 2005, and that, IMHO, was probably pushing it.
Anyhow, FWIW, you are getting it right :)
57. NETDR at 08:02 AM on 22 September, 2010Archiesteel 55
RE: Strawman defense:
I had never before read Pat Michaels views on the subject. Selecting his extreme views as a straw-man to do battle with is lame. They in no way reflect my views or any skeptics I know of.
Reading the graph of Dr Hansen's predicted warming and the climates refusal to co-operate with him doesn't take a PhD. Anyone with the ability to do simple math can figure out how wrong he was. See my previous posts.
Actual temperature was below scenario "C" which was with carbon taxes and restrictions.
I don't have to have any particular view of AGW to believe that only 44 % of the predicted warming occurred between 1988 and 2009. That is a fact. Some other parameter could be wrong, the only thing we know for sure is that the answer was wrong.
The rest is just speculation.
By the way at that [1988 to 2009] rate of warming in 100 years turns out to be about 1 ° C which would be beneficial.
My having a particular belief of climate sensitivity or use this article. is a false choice. You spin fallacy after fallacy, Who needs this article to prove what almost any high school student can compute for himself?
Far from being Boolean a model which predicts so much warming that only 44 % of it occurs is broken. There is a big difference between being close and the miserable performance of his model so far.
The errors compound so by 100 years from now the error will be huge.
Better luck on the net model. Just don't post the results where the public can compare them with reality.
58. dana1981 at 09:16 AM on 22 September, 2010Albatross and archiesteel are correct. Apparently it would have behooved me to pull a Michaels and erase Scenarios A and C from the figure, because so many people can't get past "it looks like C!". Scenario C is irrelevant because it does not accurately reflect the actual emissions, unlike Scenario B, which is quite close. The fact that actual temps have been close to those in Scenario C doesn't matter in the least.
Joe Blog nailed the problem in #44: "Im not drawing any other conclusion from this, other than Hansen had it wrong in 88."
That's the problem with Joe, angusmac, NETDR, etc.
The entire purpose of this rebuttal was to go beyond that grossly oversimplified and frankly useless conclusion. Of course Hansen didn't perfectly project the future warming rate. The question is why not? The answer is that his model's climate sensitivity was too high.
No, Hansen's model was not perfect. Yes it was off by around 25%. But that's a useless conclusion. Climate models weren't perfect 22 years ago, what a newsflash. The useful conclusion is that this tells us that the actual climate sensitivity is in the ballpark of 3.4°C for 2xCO2, which is right in the middle of the IPCC range, and approximately the average climate sensitivity of today's climate models.
Also given the fact that Hansen's model could have projected anything from rapid cooling to no change to rapid warming, being off by 25% on the warming trend really ain't that bad.
59. dana1981 at 09:21 AM on 22 September, 2010NETDR # 57 - "I don't have to have any particular view of AGW to believe that only 44 % of the predicted warming occurred between 1988 and 2009. That is a fact."
No, actually it's not even remotely a fact. Generally speaking, for something to be a fact, it has to be true.
The correct statement is that *77%* of the *projected* warming between 1988 and 2010 occurred. You'll never get the correct figure by cherrypicking the data points you like; you have to look at the trends (0.26°C per decade vs. 0.20°C, as discussed in the article).
60. NETDR at 09:45 AM on 22 September, 2010Dana 59
Using 5 year averages to avoid cherry picking.
The chart predicts[1988-2009] .9 °C - .25 °C = .65°C warming.
Reality [1988 to 2009] is .54 - .25 = .29 °CUsing GISS's own data.
Predicted warming = .29/.65 = 44.6 %
Where you got the 77 % I will probably never know.
Dr Hansen picked this particular cherry. He should know that the climate is a negative feedback system [as defined in physics not climatology] Since it was warming in the years
just before 1988 a cooling was inevitable. He should have factored that in.
An overshoot like 1998 was followed by an undershoot in 1999 and 2000 it is predictable in negative feedback systems.
[Climatology defines positive feedback differently than all of the other sciences.]
When "the debate is over" and you know all of the answers you have to know all of the answers.
61. archiesteel at 10:20 AM on 22 September, 2010@NETDR: So, just to be clear, you *don't* agree with Michaels when he says "the forecast made in 1988 was an astounding failure."
I'm just trying to establish your position here. It's kind of tricky with deniers (which you clearly are, by your approach and choice of rhetoric).
"Reading the graph of Dr Hansen's predicted warming and the climates refusal to co-operate with him doesn't take a PhD."
Actually - and this is the whole point of the article - the climate "sort of" cooperated with his assessment, i.e that temperatures were going to go up by a significant amount. He overestimated the final result, but got it mostly right compared to, say, someone who would have argued it was going to be cooling, or that temperatures were going to stay the same.
Your absolutism fools no one, you know...
"My having a particular belief of climate sensitivity or use this article. is a false choice."
Of course not. It's simple logic: either you think the argument is scientifically valid, or you don't. You just want to cherry-pick the parts you like, and ignore the parts you don't. Typical.
"You spin fallacy after fallacy,"
I certainly do not. You, on the other hand, are clearly trying to push an agenda.
"Far from being Boolean a model which predicts so much warming that only 44 % of it occurs is broken."
Not 44%. The error was 0.8 on 3.4, so about 1/4. Hansen got it about 75% right. But keep on ignoring the arguments presented to you, and restating the same faulty calculation. You're really gonna go far with that one.
62. Albatross at 10:23 AM on 22 September, 2010NETDR @60,
"Where you got the 77 % I will probably never know."
Try this: 0.20/0.26 = ....
Actually, I disagree slightly with Dana and suggest that for 1984-2009, 73% of the predicted warming was realised (0.19/0.26). But there are those error bars in the observed and predicted warming, so I should not nit pick at differences of 0.01 C when the error bars are
How about, approximately 75% of the predicted warming between 1984 and 2009 was realised.
63. scaddenp at 10:41 AM on 22 September, 2010Swinging back to the original point of this article, its about misrepresentation.
Claiming the temperature results from high emission scenario were Hansen's prediction and comparing that curve to actual temperatures which are actually more relevant to a different scenario is out and out dishonest. Redtrawing the graph so that those "confusing" other curves which would give a clearer picture shows this was a deliberate attempt to mislead.
Hansen on the other hand is giving the results for the best climate model available at the time. He didnt CHOOSE a sensitivity of 4.2 - this is an output from the model. Are we surprised that model got it wrong considering how primitive it was? No, and we now understand why it was wrong too. We still struggle to get an accurate number for short-term (10-30 year) climate sensitivity. An imperfect model is not dishonesty.
64. dana1981 at 10:44 AM on 22 September, 2010NETDR - if you don't know where I'm getting 77% then you've read neither the article nor my comments (or can't divide 0.20 by 0.26, as Albatross illustrates). I have no idea where you're getting yours from - cherrypicking favorable data points no doubt.
Albatross - I explain in the article why I use 0.20. It's the 'surface air temperature' issue and how that's defined. But using 75% is fine, I like rounding.
I guess my problem here is that I'm expecting readers and commenters at Skeptical Science to think like skeptical scientists. A skeptical scientist does not say "Hansen was wrong and I don't care why." That's incredibly unscientific.
It's critical to know what is responsible for scientific inaccuracies. For example, why was the UAH satellite temperature data so radically different from surface station data a decade ago? Were the satellites wrong? Were the surface stations wrong? Was somebody fudging the numbers or screwing up the analysis? No scientist would simply say "oh well the temperature data is just wrong and I don't care why."
I think the problem here is clearly that "Hansen was wrong" is a much more convenient conclusion for certain biased individuals than "Hansen's results are evidence that the IPCC and today's climate models have the climate sensitivity right".
65. archiesteel at 10:50 AM on 22 September, 2010@NETDR: "Using 5 year averages to avoid cherry picking."
To avoid cherry picking, use the linear trends for both Scenario B and the temp record. Using averages but arbitrarily choosing dates is still cherry-picking.
66. Albatross at 11:40 AM on 22 September, 2010Dana @64.
Mea culpa Dana. Sorry. I really need to stop multi-tasking. As you noted, you state in the post:
"So we'll assume that the global surface air temperature trend since 1984 has been one of 0.20°C per decade warming."
67. actually thoughtfull at 12:21 PM on 22 September, 2010NETDR @484.2-3.4=.8/4.2 = 0.19=19% = that is how much Hansen is off from reality.
You keep coming up with 44% by "eyeballing" .9 where .9 does not exist. What is the point of discussing if you don't keep your posts based in reality?
68. Anne van der Bom at 16:02 PM on 22 September, 2010I must have got this seriously wrong. AFAIK climate sensitivity is an outcomeof the climate models, not an input.
69. actually thoughtfull at 17:22 PM on 22 September, 2010There is a very interesting phenomena at work here - not just restricted to the deniers. Hansen's 1988 graphs show 3 lines, based on 3 sets of inputs. We all (except for Michaels - but it is 2010 - I personally have no time for those that deny the world is warming)... so we easily rule out scenario "A" - neither the emissions nor the temperatures line up - so out the window it goes.
Dana1981 presents the information, with technical support. I think I am accurately paraphrasing Dana1981 to say: Only scenario B is worth looking at - because that is a pretty close match to actual emissions. Scenarios A and C are provided for completeness and context, but are not germane to the discussion."
Many readers (and I include myself) need at least an acknowledgement that actual temperatures are at/near/below Scenario C (or to have our noses dragged through the point that "C" doesn't matter BECAUSE the actual emissions don't match that Scenario).
I know realize that the whole point is to compare Scenario B temperatures to reality, because Scenario B matches the emissions - but my first reading I was wondering why Scenario "C" - which looks like a good match (based on temperature), is irrelevant.
I think this is the difference between rigorous scientific thinking, and interested bystander thinking.
Anyways, it is one reason why I like this blog - thank you for making that point clear to me!
Regarding my post 67 comes up with 19% because I choose 4.2 for the denominator. I think that is valid because it is Hansen's error divided by Hansen's choice - rather than Hansen's error divided by reality - mine is internally consistent. But I grant that it is pretty much semantics at this point.
Finally - for anyone to look at this and be anything but amazed that someone, in 1988 - when all the theories of climate that EVENTUALLY became AGW were still in the "maybe" column and not be amazed at how prescient and accurate Hansen was, just befuddles me!
70. HumanityRules at 00:10 AM on 23 September, 2010John, is there an assumption in your calculations that 100% of the temperature rise over this period is due to the forcing of human GHGs?
Because the IPCC's "most" is starting to look like "all".
71. HumanityRules at 00:16 AM on 23 September, 2010The other question I have is to do with scenario A, B and C. Having read the paper I'd sort of assumed that A was the "business as usual" option and the catastrophists really on this for the fearful future. Is this a wrong assumption on my part?
72. Berényi Péter at 00:16 AM on 23 September, 2010Posted by dana1981 on Monday, 20 September, 2010 at 11:38 AMHad Hansen used a climate model with a climate sensitivity of approximate 3.4°C for 2xCO2 (at least in the short-term, it's likely larger in the long-term due to slow-acting feedbacks), he would have projected the ensuing rate of global surface temperature change accurately. Not only that, but he projected the spatial distribution of the warming with a high level of accuracy.
OK, let's have a closer look. Hansen 1988 has also predicted the decadal mean temperature change for scenario B as a function of pressure and latitude.
Now, since then we have got some actual data about this temperature trend distribution. The Hadley Centre of the UK Met Office has a near real-time updated dataset called HadAT (globally gridded radiosonde temperature anomalies from 1958 to present).
Linear trends in zonal mean temperature (K/decade) in HadAT2 1979-2009. 1000 hPa data are from HadCRUT2v subsampled to the time-varying HadAT2 500hPa
availability
The image above is explained in this publication:
Internal report for DEFRA, pp. 11HadAT: An update to 2005 and development of the dataset websiteColeman, H. and Thorne, P.W.
As you can clearly see, predicted and observed zonal trends have nothing to do with each other: neither high, nor low level of accuracy can be detected. Particular attention should be payed to the cooling trend in the tropical mid-troposphere (-0.5°C/century) and the severe cooling between 65S and 70S along the entire air column (down to -5°C/century). These features are absolutely lacking in Hansen's prediction, therefore the take-home message should be "Hansen's 22 year old prediction is falsified".
We can talk about if anthropogenic global warming theory were wrong on which the model was based or it was a flawed implementation, but there is no question about Hansen's failure.
BTW, the tropical upper tropospheric cold spot observed and documented in HadAT2 is inconsistent with surface warming according to even the most recent computational climate models. So neither Hansen nor his followers can get the sign of change right in some particularly important regions. Taking into account this wider failure, we can safely
bet "climate models and the anthropogenic global warming theory are wrong", quite independent of Hansen's 1988 blunder.
73. HumanityRules at 00:19 AM on 23 September, 2010Sorry Dana I didn't see you were the author. #70 is aimed at you.
74. Badgersouth at 00:51 AM on 23 September, 2010@Albatross:
On the one hand, I can understand why it is important to debunk all of the false charges made about the validity of forecasts made by Dr. James Hansen in 1998.
On the other hand, given how far the state-of-art in climate modeling has advanced over the past two decades plus, why is the validity of forecasts made in 1998 cause for such consternation today?
I’m not a scientist. I’m just trying to learn the lay of the land so to speak.
75. Albatross at 01:24 AM on 23 September, 2010Hi Badger,
Good question. The only reason I can think of is because to this day "skeptics" and those in denial about AGW keep touting Hansen's projection as "evidence" that climate models do not work at all. Or, that the projections were "wrong" then and so they will all be wrong now-- silly logic, but for those not in the know such statements are at the very least confusing and/or sow doubt, especially when not provided context or updates on the latest developments.
So sadly, people like John and Dana have to spend their valuable time addressing the confusion and trying to undue the confusion.
A perfect analogy for this Hansen paper is the 1998 Hockey Stick paper (MBH98), MBH98 did have some issues (like all seminal techniques it was not perfect), but he science has advanced (in part b/c of that seminal work) and technique shave been improved upon or refined, yet the contrarians to this day are still stuck 1998, or is that 1988?
My suggestion to NETDR, BP and HR (and HR enough with the rhetoric already HR (e.g., "catastrophists") is to please move on.
76. dana1981 at 01:33 AM on 23 September, 2010Anne van der Bom - you are correct, and I tried to be careful in my phrasing. Hansen employed a climate model which had a climate sensitivity of 4.2°C for 2xCO2.
actually thoughtfull - you got it. All Scenarios are included for completeness, but it really only makes sense to look at B. We could look at C and adjust for the differences in GHGs there too, but there's no much point, since B is closer to reality.
As for the percentages, Hansen's model sensitivity was off by 19% and his temp projections were off by 23%, the difference being the 5-10% excess in Scenario B forcing as compared to actual forcing.
HumanityRules - approximately 100% of the temp change since 1984 has been to GHGs. The IPCC looks at the temp change over a longer period of time, which has been partially
Scenario A is constantly accelerating GHG emissions, whereas B is a linear increase in emissions. Thus Scenario B is effectively business as usual.
Berényi Péter - the tropical toposphere remains a question mark, whether the cooling you discuss even exists or if it's an error in the data. With all the correct projections made by Hansen (high accuracy in spatial distribution, within 23% of the warming trend), to claim his 'prediction was falsified' because one aspect may or may not be there is ridiculous. That's like saying getting 90% on a test is an F because it's not 100%.
Badgersouth - it's worthwhile to examine the accuracy of climate models 22 years ago, because even though they've vastly improved since then, they're still based on the same fundamental physics.
77. Badgersouth at 02:16 AM on 23 September, 2010In the interest of full disclosure…
I am the one who prodded the NETDR to post on this comment thread.
During the course of the past four weeks or so, the NETDR and I have been mud wrestling about global warming/climate change on the comment threads of relevant articles posted on the website of USA Today.
Since he has repeatedly badmouthed Dr. Hansen and his projections, I wanted to see how he would fare in “debating” with individuals who have legitimate expertise in these matters. Some of you have proven my contention that the NETDR’s assertions are akin to blocks of Swiss cheese.
If any you are gluttons for punishment, you can check out my most recent marathon debate with the NETDR by going to:
78. Albatross at 02:37 AM on 23 September, 2010BP @,
Really, do you honestly want to go down this path?
FIRST, the caption in one of the figures that you provided says it is for 2010s (i.e., 2010-2020). Well, is is now only 2010, and the data you showed go to 2009. So how about we compare apples with apples and remove that Figure?
SECOND, there are way too few data points south of 45 S in the southern hemisphere to form a coherent picture.
THIRD, by cherry picking these particular data, you are neglecting the recent and valuable work undertaken by several scientists on discrepancies between the satellite, RATPAC and AOGCM data. The data need to be placed in the appropriate context (Santer 2005, Trenberth 2006, Allen 2008, Haimberger 2008, Sherwood 2008, Titchner 2009, Bengstsson 2009)
FOURTH, The GCM that Hansen used was incredibly coarse grid spacing in the horizontal (8 degress by 10 degrees; one degree is about 110 km, so the grid spacing was near 1000 km) and also in the vertical, so the model would smooth out features. As if that were not enough of an impediment, Hansen et al note that "Horizontal heat transport by the ocean is fixed at values estimated for today's climate, and the uptake of heat perturbations by the ocean beneath the mixed layer is approximated as vertical diffusion". It was not even a truly coupled atmosphere-ocean model. The fact that the model did as well as it did given that is a testament to the robustness of the underlying physics and Hansen's team. In view of the coarse grid spacing, the validation data should be on the same (or similar) grid spacing.
Now two conclusions from Hansen et al.'s abstract which are relevant to this discussion:
1) "The greenhouse warming should be clearly identifiable in the 1990s; the global warming within the next several years is predicted to reach and maintain a level at least three standard deviations above the climatology of the 1950s"
Verified by observations. For example, see Santer et al. (2003,2005). Also see various surface and tropospheric temperature data sets.
2) "Regions where an unambiguous warming appears earliest are low-latitude oceans, China and interior areas in Asia, and ocean areas near Antarctica and the north pole"
Verified-- for example, see the maps provide by Dana in the post. We have also observed-- Polar amplification, warming over continental land masses in N. hemisphere. The southern oceans have also been warming, albeit at a slower pace-- new research from the University of Washington is showing that the warming in the southern oceans extends down very deep. Read more here
79. muoncounter at 02:42 AM on 23 September, 2010All this wrangling over whether Hansen was 23% or 19% off seems to me to miss two basic points: -Way back at #5, mwof pointed out that the cooling effects of the Pinatubo eruption should be factored out of the comparison, as it effectively delayed the conditions necessary for continued heating. There is no way the effects of the eruption could have been predicted or modeled accurately and that renders such quantitative comparison moot.-Any claim that Hansen was off by 300% or 'got it wrong' is blatant nonsense. Whether you choose B, C or something in between, 300% error just isn't there. B predicts ~.7 deg rise by 2010; LOTI shows it to be ~.6. There's no significance to the second decimal place.
80. angusmac at 02:45 AM on 23 September, 2010Dana1981, am I missing something here?
My contention is quite simple: real world emissions are following Scenario B whilst real world temperatures are following Scenario C.
I thought that real (sceptical) science was about making observations, postulating a hypothesis and testing that hypothesis against the real world. If the hypothesis is not in good agreement with real world observations then it should be amended until a reasonable agreement is reached.
Currently the hypothesis which supports Scenario B is not in good agreement with real world temperature measurements. Therefore it is either a poor hypothesis at best or it is incorrect at worst. Either way it should be amended.
Hansen 2005 stated that Scenario B "was on the money." Now it looks as though Scenario C "is on the money." Consequently, if real world trends continue to follow Scenario C then computer model forcing and consequential temperature increases should be revised downwards to match real world observations.
81. Badgersouth at 02:58 AM on 23 September, 2010In the context of this discussion thread and the one associated with the article about Dr. Roger Pielke Sr’s pronouncements about OHC, I have a question.
Are any of the current crop of climate models designed to forecastof how the heat content of the sub-systems comprising the climate will change under different GHG forcing scenarios?
82. Ned at 03:10 AM on 23 September, 2010angusmac writes: If the hypothesis is not in good agreement with real world observations then it should be amended until a reasonable agreement is reached.
Yes. And as dana1981 has repeatedly pointed out, the "hypothesis" here is basically that temperature would rise at a rate corresponding to a climate sensitivity of 4.2C per doubling of CO2. The observed trend suggests that this is too high, and that a value of 3.4C per doubling would be a better fit.
Can we all agree on this?
FWIW, 3.4C/doubling falls nicely within the IPCC's estimated range for climate sensitivity.
83. Badgersouth at 03:11 AM on 23 September, 2010I presume that Dr, Hansen and his team have maintained a log of changes they have made to the forecasting model they used in 1998.
Is the log in the public domain?
84. Tom Dayton at 03:14 AM on 23 September, 2010angusmac, the "hypothesis" has been amended--considerably! The models currently "use" a sensitivity lower than the one Hansen used. I put "use" in quotes because the models do not take the sensitivity as an input; the net effect of all the factors in the models is summarizable as a sensitivity. But those amendments were not made simply as a reaction to the mis-prediction of the original model. Instead, the models started to be improved long before any meaningful evaluation of the accuracy of Hansen's prediction could be done. The improvements continue to be made to the underlying physics of the models.
The "hypothesis" that is most important is that temperatures were predicted to rise, and have, as opposed to being unchanged or dropping. Less important is the exact rate of rise. Of course the rate is important, which is why research continues urgently.
85. dana1981 at 03:16 AM on 23 September, 2010angusmac - yes, you're missing about 90% of my article.
The issue has been amended. We don't currently believe that 4.2°C is the correct short-term climate sensitivity for 2xCO2, we believe it's around 3°C, which is confirmed by comparing Hansen's results to reality. I'd really prefer not to have to repeat this for a sixth time.
Scenario C is irrelevant. It's "on the money" because its' a combination of a too-low forcing
and a too-high sensitivity. Saying C is on the money is like saying if I go twice the speed limit and then half the speed limit, I was going the right speed the whole time.
86. Albatross at 03:16 AM on 23 September, 2010Angusmac,
You claim, "If the hypothesis is not in good agreement with real world observations then it should be amended until a reasonable agreement is reached."
The physics behind GHG forcing is a theory, not a hypothesis. Same holds true for the theory of anthropogenic climate change. The challenging part is getting models to simulate the complex climate system on the planet, and then seeing how the system responds to changes in internal and external forcing mechanisms. Models are wonderful resources b/c they permit one to undertake carefully planned experiments, and that is what Hansen et al. tackled in 1988. How might the climate system respond to increasing radiative forcing from GHGs?
The 1988 paper was seminal, but as is often the case for seminal works, it was imperfect-- and Hansen et al. fully realized that much. The science (and models) has advanced since then...it seems it is only the skeptics who are stuck in 1988. It was through a combination of huge leaps in computing resources, better code, and by considering new data and advances in the science that modelers have been able to dramatically improve the models. The new generation of AOGCMs even include atmospheric chemistry.
While the model in 1988 was imperfect, it certainly was not nearly as imperfect as some contrarians have elected to falsely state on the public record. That is what this whole post is about-- I really cannot understand why some people cannot see that.
So Angus, you have the wrong end of the stick when you and others keep claiming that keep claiming that it is the scientists who are stuck in the past and not moving on.
What you are complaining about in the quote (that I cited above) is actually exactly what scientists continue to strive towards.
PS: Are you familiar with the Earth Simulator 2 project in Japan?
87. dana1981 at 03:17 AM on 23 September, 2010Tom Dayton - well said.
88. Albatross at 03:42 AM on 23 September, 2010Badger @83,
Maybe this will help.
Dana and Tom,
What you said :) Current equilibrium climate sensitivity for the GISS model is about 2.7 C. More info here.
89. archiesteel at 03:44 AM on 23 September, 2010@angusmac: please re-read my response to this at #55. If you don't understand parts of it, please tell me.
90. Anne van der Bom at 05:43 AM on 23 September, 2010muoncounter #79
Actually, scenario B and C had an ‘El Chichon’ sized volcanic eruption in 1995. Pinatubo was much larger (about 4x I believe), so your point is still valid.
The only way to deal with this is do multiple model runs, based on different scenarios. The inclusion of one or more volcanic eruptions then becomes part of those scenarios alongside the emissions.
91. muoncounter at 06:27 AM on 23 September, 2010#90: "scenario B and C had an ‘El Chichon’ "
Yes, angusmac's refurbished graph shows the model runs with a one year dip; Pinatubo (and the LOTI curve) was more like 2-3 years (see Robock 2003). I'd assume there were more model runs and only these 3 made the paper.
92. Badgersouth at 07:11 AM on 23 September, 2010@ Albatross:
Thanks for the link to the GISS webpage.
Where can I find a laundry list of the current generation of climate models, i.e., the ones that the IPCC will use in the new assessment process now getting underway?
93. kdkd at 08:15 AM on 23 September, 2010BP #72
I'm sorry, but that's really not good enough. Comparing charts by eyeball like that is so ridden with pitfalls of subjectivity (conformation bias, perceptual bias and so on) the only way you can hope to offer a valid comparison is through statistical comparisons. And that's even before accounting for Albatross' comments at #78, which suggests that even if quantified your analysis would be invalid in any case.
As I've said previously, if you want to be taken seriously, you've got to do much much better than this in terms of the way you go about assessing the evidence.
94. Albatross at 08:54 AM on 23 September, 2010Badger,
You are welcome. Follow the second link in my post @88 ("more info here").
95. scaddenp at 09:13 AM on 23 September, 2010Badger, for the AR5, you are look for PCMDI participants
96. Berényi Péter at 20:39 PM on 23 September, 2010#93 kdkd at 08:15 AM on 23 September, 2010I'm sorry, but that's really not good enough. Comparing charts by eyeball like that is so ridden with pitfalls of subjectivity (conformation bias, perceptual bias and so on) the only way you can hope to offer a valid comparison is through statistical comparisons. And that's even before accounting for Albatross' comments at #78, which suggests that even if quantified your analysis would be invalid in any case.
No need for confabulation. The situation is more serious than you claim. It's definitely not
an optical illusion and it is not just a weakness of Hansen 1988, but much more pervasive, plaguing effectively all computational climate models since then, irrespective of implementation details and any impressive advance in computing power.
The study below shows beyond reasonable doubt that even quite recent models (not a few but 22 of them) are inconsistent with observations in this respect and not just with the HadAT2 dataset, but also with three others (RATPAC [Radiosonde Atmospheric Temperature Products for Assessing Climate], IGRA [Integrated Global Radiosonde Archive] & RAOBCORE[RAdiosonde OBservation COrrection using REanalyses]).
Consistency is only found at the surface, but we do know how surface data are picked & adjusted ad nauseam on the one hand while the very selection criterion for model set used in this study was consistency with surface temperature datasets on the other hand, so no wonder they match on this single point.
All this evidence points to some robust problem not only in individual models, but also in the underlying AGW theory all otherwise independent computational climate models are based on.
International Journal of ClimatologyVolume 28, Issue 13, pages 1693–1701, 15 November 2008DOI: 10.1002/joc.1651A comparison of tropical temperature trends with model predictionsDavid H. Douglass, John R. Christy, Benjamin D. Pearson, S. Fred SingerArticle first published online: 5 DEC 2007
"Our results indicate the following, using the 2σSE criterion of consistency:(1) In all cases, radiosonde trends are inconsistent with model trends, except at the surface.
(2) In all cases UAH and RSS satellite trends are inconsistent with model trends.(3) The UMD T2 product trend is consistent with model trends."
"Evidence for disagreement: There is only one dataset, UMD T2, that does not show inconsistency between observations and models. But this case may be discounted, thus implying complete disagreement. We note, first, that T2represents a layer that includes temperatures from the lower stratosphere. In order for UMD T2 to be a consistent representation of the entire atmosphere, the trends of the lower stratosphere must be significantly more positive than any observations to date have indicated. But all observed stratospheric trends, for example by MSU T4 from UAH and RSS, are significantly negative. Also, radiosonde trends are even more profoundly negative – and all of these observations are consistent with physical theory of ozone depletion and a rising tropopause. Thus, there is good evidence that UMD T2 is spuriously warm."
"Our view, however, is that the weight of the current evidence, as outlined above, supports the conclusion that no model-observation agreement exists."
So. The take-home message is "no model-observation agreement exists".
The most likely candidate for explaining model failure is insufficient theoreticaltreatment of deep moist convection of course (and ample production of extremely dry air parcels by association).
Why is it important? Because Douglass at al. also write:"If these results continue to be supported, then future projections of temperature change, as depicted in the present suite of climate models, are likely too high."
They can't help but say it, as it is the case. Climate sensitivity to changes in levels of well mixed gases showing some opacity in restricted bands of thermal IR is consistently overestimated by computational models.
97. kdkd at 21:06 PM on 23 September, 2010BP #96
Given your recent history of invalid analysis, and refusal to provide your data for checking (and thus laying yourself open wide open to accusations of scientific fraud) you'll excuse my cynicism when examining your argument.
In this case, I want to see more published examples of large scale evaluations of climate models. And more importantly I want you to present quantified estimates of model precision and bias, not the vague insinuations that you have presented.
Finally, I'm not sure that validating the model against absolute temperature would be the best procedure. Given calibration problems and the fact that these complex systems are very likely sensitive to initial conditions (modeled and observed in quite different ways in all likelihood), the agreement between modeled relative change in temperature ovr time versus observed relative change in temperature over time looks not too bad (although I'd have to evaluate that with a chi squared test of goodness of fit to be sure).
98. Riccardo at 21:14 PM on 23 September, 2010Berényi Péter,"The study below shows beyond reasonable doubt [...]"not quite so, indeed:
http://www.skepticalscience.com/tropospheric-hot-spot.htmhttp://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/They even used an outdated RAOBCORE dataset version; right or wrong they may be, they for sure should have used the last version available or justify the choice (which they didn't).
99. Albatross at 01:54 AM on 24 September, 2010BP,
Pardon my skepticism, but it really does not help your cause presenting a paper co-authored by Singer and Douglass. Regardless, you continue to argue a straw man BP-- this post is not about the tropospheric hot-spot, and I am surprised that John has not deleted your posts for being OT-- if you want to speak to that, please go to the appropriate thread (see Riccardo's post for links). Second, several papers have recently come out which have superseded the Douglass paper (see my post @78). Why ignore those and cherry-pick Douglass? And why include Douglass et al's paper above when you know that there data and analysis had significant issues?
And as for your comment about the inability of GCMs to simulate convection. Well, yes that was a tad difficult for Hansen et al. with a 1000 km grid spacing. One can use a good CPS (e.g., Kain-Fritsch) at smaller grid spacing (say, 50 km), and explicitly model convection at grid spacing <3 km. They are running the operational ECMWF global model at about 16 km horizontal grid-spacing right now, so it is going to be some time yet before modelers can address the deep, moist convection issue.
In the mean-time the planet continues to warm at a rate very close to that predicted in the various IPCC reports.
One final note, one does not need a climate model to infer ECS to doubling of CO2. Many proxy records which implicitly include all the feedbacks and processes point to a EQS of +3 C. You know that, yet you posts on this thread seem a determined effort to convince the unwary that the models have no skill and will predict too much warming based on issues surrounding both the observation and modelling of the tropical hot spot feature.
100. archiesteel at 02:21 AM on 24 September, 2010@BP: "Consistency is only found at the surface, but we do know how surface data are picked & adjusted ad nauseam on the one hand while the very selection criterion for model set used in this study was consistency with surface temperature datasets on the other hand, so no wonder they match on this single point."
You shouldn't be accusing others of scientific fraud when you are yourself suspected of the same thing.
I personally will be ignoring any argument you put forth until you've convincingly addressed the glaring errors in your previous (and contentious) analysis.
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A detailed look at Hansen's 1988 projectionsHansen et al. (1988) used a global climate model to simulate the impact of variations in atmospheric greenhouse gases and aerosols on the global climate. Unable to predict future human greenhouse gas emissions or model every single possibility, Hansen chose 3 scenarios to model. Scenario A assumed continued exponential greenhouse gas growth. Scenario B assumed a reduced linear rate of growth, and Scenario C assumed a rapid decline in greenhouse gas emissions around the year 2000.
Misrepresentations of Hansen's Projections
The 'Hansen was wrong' myth originated from testimony by scientist Pat Michaels before US House of Representatives in which he claimed "Ground-based temperatures from the IPCC show a rise of 0.11°C, or more than four times less than Hansen predicted....The forecast made in 1988 was an astounding failure."
This is an astonishingly false statement to make, particularly before the US Congress. It was also reproduced in Michael Crichton's science fiction novel State of Fear, which featured a scientist claiming that Hansen's 1988 projections were "overestimated by 300 percent."
Compare the figure Michaels produced to make this claim (Figure 1) to the corresponding figure taken directly out of Hansen's 1988 study (Figure 2).
Figure 1: Pat Michaels' presentation of Hansen's projections before US
Figure 2: Projected global surface air temperature changes in Scenarios A, B, and C (Hansen 1988)
Notice that Michaels erased Hansen's Scenarios B and C despite the fact that as discussed above, Scenario A assumed continued exponential greenhouse gas growth, which did not occur. In other words, to support the claim that Hansen's projections were "an astounding failure," Michaels only showed the projection which was based on the emissions scenario which was furthest from reality.
Gavin Schmidt provides a comparison between all three scenarios and actual global surface temperature changes in Figure 3.
Figure 3: Hansen's projected vs. observed global temperature changes (Schmidt 2009)
As you can see, Hansen's projections showed slightly more warming than reality, but clearly they were neither off by a factor of 4, nor were they "an astounding failure" by any reasonably honest assessment. Yet a common reaction to Hansen's 1988 projections is "he overestimated the rate of warming, therefore Hansen was wrong." In fact, when skeptical climate scientist John Christy blogged about Hansen's 1988 study, his entire conclusion was "The result suggests the old NASA GCM was considerably more sensitive to GHGs than is the real atmosphere." Christy didn't even bother to examine why the global climate model was too sensitive or what that tells us. If the model was too sensitive, then what was its climate sensitivity?
This is obviously an oversimplified conclusion, and it's important to examine why Hansen's projections didn't match up with the actual surface temperature change. That's what we'll do here.
Hansen's AssumptionsGreenhouse Gas Changes and Radiative Forcing
Hansen's Scenario B has been the closest to the actual greenhouse gas emissions changes. Scenario B assumes that the rate of increasing atmospheric CO2 and methane increase by 1.5% per year in the 1980s, 1% per year in the 1990s, 0.5% per year in the 2000s, and flattens out (at a 1.9 ppmv per year increase for CO2) in the 2010s. The rate of increase of CCl3F and CCl2F2 increase by 3% in the '80s, 2% in the '90s, 1% in the '00s, and flatten out in the 2010s.
Gavin Schmidt helpfully provides the annual atmospheric
concentration of these and other compounds in Hansen's Scenarios. The projected concentrations in 1984 and 2010 in Scenario B (in parts per million or billion by volume [ppmv and ppbv]) are shown in Table 1.
Table 1: Scenario B greenhouse gas (GHG) concentration in 1984, as projected by Hansen's Scenario B in 2010, and actual concentration in 2010
GHG 1984 Scen. B 2010 Actual 2010
CO2 344 ppmv 389 ppmv 392 ppmv
N2O 304 ppbv 329 ppbv 323 ppbv
CH4 1750 ppbv 2220 ppbv 1788 ppbv
CCl3F 0.22 ppbv 0.54 ppbv 0.24 ppbv
CCl2F2 .038 ppbv 0.94 ppbv 0.54 ppbv
We can then calculate the radiative forcings for these greenhouse gas concentration changes, based on the formulas from Myhre et al. (1998).
Total Scenario B greenhouse gas radiative forcing from 1984 to 2010 = 1.1 W/m2
The actual greenhouse gas forcing from 1984 to 2010 was approximately 1.06 W/m2 (NASA GISS). Thus the greenhouse gas radiative forcing in Scenario B was too high by about 5%.
Climate Sensitivity
Climate sensitivity describes how sensitive the global climate is to a change in the amount of energy reaching the Earth's surface and lower atmosphere (a.k.a. a radiative forcing). Hansen's climate model had a global mean surface air equilibrium sensitivity of 4.2°C warming for a doubling of atmospheric CO2 [2xCO2]. The relationship between a
change in global surface temperature (dT), climate sensitivity (λ), and radiative forcing (dF), is
dT = λ*dF
Knowing that the actual radiative forcing was slightly lower than Hansen's Scenario B, and knowing the subsequent global surface temperature change, we can estimate what the actual climate sensitivity value would have to be for Hansen's climate model to accurately project the average temperature change.
Actual Climate Sensitivity
One tricky aspect of Hansen's study is that he references "global surface air temperature." The question is, which is a better estimate for this; the met station index (which does not cover a lot of the oceans), or the land-ocean index (which uses satellite ocean temperature changes in addition to the met stations)? According to NASA GISS, the former shows a 0.19°C per decade global warming trend, while the latter shows a 0.21°C per decade warming trend. Hansen et al. (2006) – which evaluates Hansen 1988 – uses both and suggests the true answer lies in between. So we'll assume that the global surface air temperature trend since 1984 has been one of 0.20°C per decade warming.
Given that the Scenario B radiative forcing was too high by about 5% and its projected surface air warming rate was 0.26°C per decade, we can then make a rough estimate regarding what its climate sensitivity for 2xCO2 should have been:
In other words, the reason Hansen's global temperature projections were too high was primarily because his climate model had a climate sensitivity that was too high. Had the sensitivity been 3.4°C for a 2xCO2, and had Hansen decreased the radiative forcing in Scenario B slightly, he would have correctly projected the ensuing global surface air temperature increase.
The argument "Hansen's projections were too high" is thus not an argument against anthropogenic global warming or the accuracy of climate models, but rather an argument against climate sensitivity being as high as 4.2°C for 2xCO2, but it's also an argument for climate sensitivity being around 3.4°C for 2xCO2. This is within the range of climate sensitivity values in the IPCC report, and is even a bit above the widely accepted value of 3°C for 2xCO2.
Spatial Distribution of Warming
Hansen's study also produced a map of the projected spatial distribution of the surface air temperature change in Scenario B for the 1980s, 1990s, and 2010s. Although the decade of the 2010s has just begun, we can compare recent global temperature maps to Hansen's maps to evaluate their accuracy.
Although the actual amount of warming (Figure 5) has been less than projected in Scenario B (Figure 4), this is due to the fact that as discussed above, we're not yet in the decade of the 2010s (which will almost certainly be warmer than the 2000s), and Hansen's climate
model projected a higher rate of warming due to a high climate sensitivity. However, as you can see, Hansen's model correctly projected amplified warming in the Arctic, as well as hot spots in northern and southern Africa, west Antarctica, more pronounced warming over the land masses of the northern hemisphere, etc. The spatial distribution of the warming is very close to his projections.
Figure 4: Scenario B decadal mean surface air temperature change map (Hansen 1988)
Figure 5: Global surface temperature anomaly in 2005-2009 as compared to 1951-1980 (NASA GISS)
Hansen's Accuracy
Had Hansen used a climate model with a climate sensitivity of approximate 3.4°C for 2xCO2 (at least in the short-term, it's likely larger
in the long-term due to slow-acting feedbacks), he would have projected the ensuing rate of global surface temperature change accurately. Not only that, but he projected the spatial distribution of the warming with a high level of accuracy. The take-home message should not be "Hansen was wrong therefore climate models and the anthropogenic global warming theory are wrong;" the correct conclusion is that Hansen's study is another piece of evidence that climate sensitivity is in the IPCC stated range of 2-4.5°C for 2xCO2.
This post is the Advanced version (written by dana1981) of the skeptic argument "Hansen's 1988 prediction was wrong". After reading this, I realised Dana's rebuttal was a lot better than my original rebuttal so I asked him to rewrite the Intermediate Version. And just for the sake of thoroughness, Dana went ahead and wrote a Basic Version also. Enjoy!
Posted by dana1981 at 11:38 AM
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Comments 101 to 121 out of 121:
101. KR at 02:48 AM on 24 September, 2010Of note in regards to the Douglass et al 2007 paper BP referred to is the rebuttal by Santer et al 2008, which states:
"Our results contradict a recent claim that all simulated temperature trends in the tropical troposphere and in tropical lapse rates are inconsistent with observations."
102. KR at 02:50 AM on 24 September, 2010Suggestion - further posts regarding the tropospheric hot spot should move to the appropriate threads, such as There's no tropospheric hot spot, as it's off topic here.
103. Philippe Chantreau at 09:47 AM on 24 September, 2010I can recall so many previous instances of BP unambiguously accusing scientists of fraud without any evidence (for instance see Ocean acidification, when such accusation stemmed from his misintepretation of the papers), it's becoming obvious that this has become an obsession of his.
As for discussing scientific evidence: in the interest of the discussion, I advocate for the the moderator to strike any and all future posts that even remotely suggests fraud if there is no supporting evidence, not only that the accused scientists/papers actually are wrong, but that they deliberately are so with an intent to deceive.
Skeptics like to talk about burden of proof but it's something they
104. doug_bostrom at 10:22 AM on 24 September, 2010The "fraud" thing is a magical incantation, a clumsy way of wishing away facts, not scientific.
105. Albatross at 12:18 PM on 24 September, 2010Philippe @104,
"I advocate for the the moderator to strike any and all future posts that even remotely suggests fraud if there is no supporting evidence"
I'll second that. The blog policy currently states that:
"No accusations of deception. Any accusations of deception, [fraud], dishonesty or corruption will be deleted. This applies to both sides. Stick to the science. You may criticise a person's methods but not their motives."
Humble suggestion is in square brackets.
Response: Fraud was implicit (doesn't that equate to deception, dishonesty and/or corruption?). Nevertheless, I've updated the Comments Policy to include fraud, just to make it explicit.
106. Albatross at 13:00 PM on 24 September, 2010Hi John,
Thanks. Yes, I agree it was implicit, but best to be clear I guess.
107. kdkd at 14:20 PM on 24 September, 2010I know this is a bit off topic, although it is in context of the present discussion.My own accusation of BP's possible engagement in scientific dishonesty or incompetence is based on data he's presented on this site. He could make the problem magically go away if he just responded to the problem, but so far he seems reluctant to do so. I don't feel particularly inclined to let this go until he does come up with the goods, as his credibility as a commentator on this site hinges on it.
108. Berényi Péter at 21:23 PM on 24 September, 2010#107 kdkd at 14:20 PM on 24 September, 2010My own accusation of BP's possible engagement in scientific dishonesty or incompetence is based on data he's presented on this site. He could make the problem magically go away if he just responded to the problem
Your perception of a "problem" is rather odd. I thought we are here to learn and understand what's going on in climate science, not to make our egos fatter. Therefore if you keep accusing me of engagement in scientific dishonesty or incompetence or even scientific fraud it is your problem, not mine. And it would not go away, magically or otherwise, no matter if I took up the gauntlet
What about doing some work yourself? I have shown you the data sources used (SEDAC/GPWv3 and GHCNv2) and also described the basic method, enough for a hint. Rest assured I know how to use and abuse statistical tests, but the thing is statistics is worthless in establishing facts until the underlying processes are understood properly. For example I have just realized the easy-to-understand tidbit there is a hysteresis between local population density and UHI effect. That is, increasing density has a more or less immediate warming effect while decreasing density shows up in a delayed manner (man made structures do not go away immediately as people move out). It is not lack of statistics that makes an argument unscientific but mistreatment of concepts.
So, if you are not willing to work, at least please stop whining. As I haveshown you a sizable UHI effect is almost inevitable in the surface temperature record while global population keeps increasing on a finite surface. How to quantify it, is another question. If you could uncover a good reason why the UHI effect should not be ergodic, that would be a true contribution (as opposed to empty accusations and talk about credibility). Debugging is not done by accusing others, but actually uncovering specific errors and supplying a patch that removes it.
I think you need a thorough understanding of the open source development cycle which is much closer to what is possible in the blogosphere than the old-fashioned scientific publication cycle with its closed peer review system. At least in software development this method is proven to be competitive with more traditional quality assurance procedures.
Of course before this kind of publication process can get useful in exchanging ideas at least some revision control infrastructure has to be put in place, but that's another story.
Anyway, if you do not do it yourself, you have to wait some more for a meaningful and transparent analysis of UHI along these lines with all the statistics you may wish for, as unfortunately I don't have much time to do it for free.
While we are at it, the inconsistency between models and observations in the tropical troposphere can be resolved in a simple way if we assume the surface temperature trend has a long term warming bias (a.k.a. UHI).
As the selection criterion of models included in Douglass 2007 was their consistency with the surface record and the "hot spot" has no any direct relation to CO2, just to surface temperatures whatever the cause behind them happens to be, if surface temperature trends are adjusted sufficiently downward, they can get consistent with both tropospheric trends and with a different set of models, selected to conform to reduced surface trends.
In this case one would select the models that somehow avoid increasing overall IR opacity between 20N and 20S in spite of some increase in opacity in the CO2 band. These are precisely the models with a negative water vapor feedback in the tropics.
109. kdkd at 21:39 PM on 24 September, 2010BP #108.
That's a very long winded attempt at justifying why you won't give me the raw data that you used to make the graph you presented. I want this so that I can assess the validity of your claim statistically. It's not possible to do so without it.
Just do it, I'll report back and then we can let it go. I don't intend to let it go otherwise, and it should be a simple job for you to release the data as it was processed by you. Your attempt at justifying why you won't do so is very poor.
Isn't this the very kind of defensive behaviour that you claim is unacceptable among the professional climate scientists?
110. kdkd at 21:46 PM on 24 September, 2010BP:
By the way, I think you'll find that I'm extremely familiar with the open source development model. I endorse it and support it for a number of uses, and argue for its use wherever possible with my colleagues, frequently quite vigorously. I'm also familiar with the problems surrounding scientific computing and the issues which cause a divergence from more traditional allegedly more rigorous software engineering practices.
I am just finishing the reviews for a paper I wrote that argues strongly for the use of an open source model, and revision control protocols (using git for what it's worth) in social science research which will hopefully be published in the Australasian Journal of Information Systems next year.
Anyway this is becoming increasingly off topic. Take home message: put up, or continue to have your credentials and motivations questioned.
111. Ned at 23:02 PM on 24 September, 2010BP writes: What about doing some work yourself? I have shown you the data sources used (SEDAC/GPWv3 and GHCNv2) and also described the basic method, enough for a hint.
The link in BP's post is to this comment. In the immediately following comment I showed that even granting all your assumptions, the UHI effect would explain around 6% to 9% of recent observed warming over land, and around 3% globally.
The analysis that kdkd has been repeatedly challenging you on was described in this other comment. Unfortunately, it is not replicable by anyone else, because you wrote in the very first sentence "I have selected 270 GHCN stations worldwide with a reasonably uniform distribution over land [...]"without identifying the specific stations.
In that comment, you wrote: But the most important finding is that there is a (not very strong) correlation between these two parameters, so a regression line can be computed.
What kdkd has been bugging you about is simply the statistical significance (or lack thereof) of that regression. You said it was "the most important finding". You also stated that the correlation was "not very strong", so it's understandable why kdkd would assume that you'd looked at the statistics for your model.
If you had saved the results of that analysis, it would be exceptionally simple to just post the F-test result or 95% confidence interval or whatever. Thus, my assumption is that you probably did the analysis in a hurry, wrote up that comment, and then didn't bother saving it.
Personally, I don't see this as a really big deal. My thoughts on BP's analysis were given here and here. My guess is that:
(1) The significance of BP's model was probably very low (low enough to make it all meaningless).
(2) The hand-picked set of stations seems to be very unrepresentative of the overall population of land stations, as I noted in the linked comments. I don't mean to suggest that this was deliberate, just that it's hard to get a representative sample.
(3) I don't think the quality of either the coordinate information in the GHCN metadata or the spatial resolution of the population density data are sufficient to actually support the type of analysis described.
Thus, I was and am still skeptical.
112. angusmac at 23:27 PM on 24 September, 2010Dana#85 Scenario C is not irrelevant. On the contrary, it is relevant because it matches actual temperatures better than the other scenarios. It may help to think of Scenario C as a “black box” that gets the right answers.
I enclose Figure 2 as explanation (click here for a high resolution image).
Figure 2: Scenarios B and C Compared with Measured GISS LOTI Data (after Hansen, 2006)
It should be noted that the emissions in Scenarios B and C are similar until 2000. Thereafter they diverge. Scenario C emissions are curtailed at their 2000 level whist Scenario B emissions continue to increase. Dana has shown that the Scenario B emissions are quite close to reality.
Nevertheless, the following points are evident from Figure 2:
1. Scenario C provides a better prediction of real temperatures than Scenario B.
2. The Scenario C warming trend for 1984-2009 is 0.24 °C/dec. This is near to the measured rate of 0.19 °C/dec and is significantly closer to reality than the Scenario B rate of 0.26 °C/dec.
3. The Scenario C prediction for 2000-2019 is nearly zero at 0.01 °C/dec. Furthermore, for the ten years that have elapsed since 2000, it appears to be “on the money.”
CONCLUSIONS
Hansen and his 1988 team are to be commended for producing models that are close to reality. Scenario C in particular has shown significant skill in predicting actual temperatures.
Additionally, Hansen’s (2006) comments on the 1988 models that,“… a 17-year period is too brief for precise assessment of model predictions, but distinction among scenarios [B & C] and comparison with the real world will become clearer within a decade [2015].”
I concur, let us wait until 2015 to see which scenario is correct. Will the “black box" that is Scenario C be right or will the real world move closer to Scenario B?
113. archiesteel at 01:09 AM on 25 September, 2010@angusmac: Scenario C is not relevant because it is based on CO2 emmissions that do not accurately represent actual, real-world emmissions.
Scenario B, however, uses figures that are close to real-world emmissions, and thus offer the same basic parameters (except for climate sensitivity).
The fact that Scenario C is closer is irrelevant, because it uses does not use real-world emmission values.
Do you understand your mistake?
114. Phil at 01:43 AM on 25 September, 2010angusmac @112
Scenarios A, B and C all represent the same "black box" - just with a different input value; the CO2 emissions for future years (his future, our past). Scenarios A B and C could be said (perhaps somewhat crudely) to correspond to predictions of different CO2 concentrations in the atmosphere in the future. Since we are now in Hansens future, we can look at the currentactual CO2 concentration in the atmosphere and determine that emissions have most closely followed Hansens scenario B. Thus scenario C (and A) is irrelevant because it was a prediction for a course of action the world did not take
115. Ned at 02:04 AM on 25 September, 2010RE: comments from myself, kdkd, and BP above:
It's off-topic for this thread, but I've just posted a lengthy "reanalysis and commentary" over in the appropriate thread (Urban Heat Islands: serious problem or holiday destination for skeptics?).
116. dana1981 at 02:37 AM on 25 September, 2010angusmac, I'll try one more time to explain to you.
The temperature change is based primarily on 2 factors, radiative forcing (which depends heavily on emissions scenarios) and climate sensitivity (which is a product of the climate model).
Regarding the first factor, Scenario B has been quite close to reality. There is no point in comparing to Scenario C, which has not. It doesn't matter if the temps follow closer to C, because the real-world emissions do not.
Since the real-world emissions and forcing have been close to B, we can then examine the second factor - climate sensitivity. As I showed in the article, we can then determine that the real-world sensitivity has been around 3.4°C for 2xCO2.
Notice my use of the term "real-world". You're obsesing with Scenario C, which is a hypothetical world which does not match the real world. Both of the factors mentioned above are incorrect in Scenario C. One is too high and one is too low. The problem is that in Scenario C, the forcing flattens out, whereas that will not happen in reality. There is simply no chance that Scenario C will continue close to reality because it does not reflect real-world emissions or radiative forcings.
117. angusmac at 19:19 PM on 25 September, 2010#102 archiesteel. Scenario B is also incorrect – it uses the right emissions but over-predicts current temperatures.
#105 Dana, you don't need to explain. I already understand the theory (hypothesis?) of AGW.
The point that I am trying to make and that you, and some others, are ignoring is that the real world is not following Scenario B. This is a case of right emissions in - wrong (too high) temperatures out.
My Figure 2 clearly shows that Scenario C is tracking the real world temperatures much better than Scenario B. This is a case of wrong emissions in - right answer out
What is required is a model that gives real world emissions in - real world temperatures out. I have not seen one yet, probably because this would mean revising radiative forcings and/or temperature sensitivity downwards from currently accepted norms.
Your statement that, "There is simply no chance that Scenario C will continue close to reality because it does not reflect real-world emissions or radiative forcings" is extremely brave.
I prefer Jim Hansen's stance to wait until 2015 to differentiate between the outcomes of Scenarios B and C. This would enable us to assess whether or not current assumptions are correct. If Scenario C still gives correct predictions then the assumed radiative forcings and/or climate sensitivity would need to be revised downwards.
118. CBDunkerson at 19:25 PM on 25 September, 2010
angusmac #117: "The point that I am trying to make and that you, and some others, are ignoring is that the real world is not following Scenario B. This is a case of right emissions in - wrong (too high) temperatures out."
Actually, 'scenario B' emissions were slightly higher than actual emissions have been... and the temperature divergence is of such short duration (5 years) as to be meaningless. This should be obvious from the fact that there are divergences that great between the scenario B temperature line and actual temperatures in the years BEFORE the paper was published.
119. angusmac at 20:04 PM on 25 September, 2010CBDunkerson #118 see angusmac #101 in which I concur with, Hansen's (2006) comments on the 1988 models that,"… a 17-year period is too brief for precise assessment of model predictions, but distinction among scenarios [B & C] and comparison with the real world will become clearer within a decade[2015]."
What Hansen was saying in 2006 is that "within a decade" means2015 - 1988 = 27 years which is a reasonable time period to compare the scenarios. The start date is from 1988 not 2010 and therefore is significantly longer than the 5 years mentioned in your post.
120. CBDunkerson at 22:30 PM on 25 September, 2010angusmac #119: "The start date is from 1988 not 2010 and therefore is significantly longer than the 5 years mentioned in your post."
Yes, but from 1988 through 2005 actual temperatures were consistent with scenario B. Ergo... 5 years of divergence (2006 - 2010).
121. archiesteel at 00:57 AM on 26 September, 2010@angusmac: "The point that I am trying to make and that you, and some others, are ignoring is that the real world is not following Scenario B. This is a case of right emissions in - wrong (too high) temperatures out."
We understand your point, it is simply wrong. We perfectly understand that Scenario B is a case of right emmissions in - wrong temps out. What the article tries to explain is how wrong (and how right) Hansen 1988 was. The only way to find out the divergence between his predictions and reality is to pick the scenario that uses parameters that are closer to reality. That scenario is scenario B.
The fact that scenario C looks closer to reality is that it contains *two* erroneous components that cancel each other out and make it appear similar to real-world outcomes (for a while, at least). It is a curiosity, a coincidence, nothing more.
"What is required is a model that gives real world emissions in - real world temperatures out. I have not seen one yet, probably because this would mean revising radiative forcings and/or temperature sensitivity downwards from currently accepted norms."
Did you even read the article? The reason Scenario 2 (near real-world emmissions in) gave inaccurate results was because of a wrong climate sensitivity value (4.2C instead of 3.4C).
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Global Warming: An Unstoppable 1,500-Year Cycle
New Book Debunks Greenhouse Fears and Points to Natural 1,500-Year Warming
Cycles
NEW YORK, Nov. 9 /PRNewswire/ -- A new book that is bound to be controversial in public policy and environmental circles says that the Earth has a moderate, natural warming roughly every 1,500 years caused by a solar- linked cycle. The current Modern Warming may be mostly due to that
natural cycle and not human activity, say the book's authors, well-known climate physicist Fred Singer and Hudson Institute economist Dennis Avery. "Unstoppable Global Warming-Every 1500 Years" (Rowman & Littlefield, 276 pages, $24.95) assembles physical and historical evidence of the natural climate cycle that ranges from ancient records in Rome, Egypt, and China; to 12,000 antique paintings in museums; to Vikings' tooth enamel in Greenland cemeteries; and to high-tech analyses of ice cores, seabed sediments, tree rings, fossil pollen and cave stalagmites. "The Romans wrote about growing wine grapes in Britain in the first century," says Avery, "and then it got too cold during the Dark Ages. Ancient tax records show the Britons grew their own wine grapes in the 11th century, during the Medieval Warming, and then it got too cold during the Little Ice Age. It isn't yet warm enough for wine grapes in today's Britain. Wine grapes are among the most accurate and sensitive indicators of temperature and they are telling us about a cycle. They also indicate that today's warming is not unprecedented." "We have lots of physical evidence for the 1,500-year cycle," says Singer. "Yet we don't have physical evidence that human-emitted CO2 is adding significantly to the natural cycle. The current warming started in 1850, too early to be blamed on industries and autos." Singer notes that humanity learned of the 1,500-year cycle only recently, from the first Greenland ice cores brought up in 1983. The cycle was too long and moderate to be observed by earlier peoples without thermometers and written records. The Greenland ice cores showed the 1,500-year cycle going back 250,000 years. It raises temperatures at the latitude of New York and Paris by 1-2 degrees C for centuries at a time, more at the North and South Poles, with a global average of 0.5 degrees C. In 1987, the first Antarctic ice core showed the cycle extending back through the last 400,000 years and four Ice Ages-and demonstrated the cycle was indeed global. There is also evidence of the 1,500-year cycle in seabed sediments from six oceans, in ancient tree rings from around the Northern Hemisphere, in glacier advances and retreats from Greenland to New Zealand, and in cave stalagmites from every continent including South Africa. The North American Pollen Database shows nine complete reorganizations of the continent's trees and plants in the past 14,000 years, or one every 1,650 years. "The deepest seabed sediment cores show the cycle has been going on for at least a million years," says Avery.
Sunspot observations over the past 400 years, along with modern analysis of carbon and beryllium isotopes, link the 1,500-year cycle to variations recently detected by satellites in the sun's irradiance. Antarctic ice studies show global temperatures tracking closely with atmospheric CO2 levels over the past 400,000 years. However, Singer and Avery note the studies also show that temperature changes preceded the CO2 changes by about 800 years. Thus, more warming has produced more atmospheric CO2, rather than more CO2 producing global warming. This makes sense, say the authors, because the oceans hold vastly more CO2 than the air, and warming forces water to release some its gases. Singer and Avery say that the science of the natural cycle runs counter to what many believe and fear will happen as a result of man-made global warming: * Wild species won't become extinct in our warming because they've been through at least 600 previous warmings, including the Holocene Warming just 5,000 years ago that was much warmer than today. * The seas won't rise to drown New York before the next cooling, because 90 percent of the world's remaining ice is in the melt-resistant Antarctic. Even a 5 degree C warming would decrease its ice mass by only 1.5 percent, over centuries. * Warming won't bring famine, because it brings what crops like -- longer growing seasons, more sunlight, and few untimely frosts. More CO2 also stimulates plants' growth, and enhances their water use efficiency. "We hope our book will help calm the rampant hysteria about global warming and the flawed Greenhouse models," emphasizes Avery. "We should be using our resources and technology to find the best ways to adapt to the inevitable but moderate warming to come, not to study one climate model after another, scare people to death, and pass crippling 'environmental' legislation that would deny the world the economic growth it needs to overcome poverty, the greatest problem of all." About Hudson Institute Hudson Institute is a non-partisan policy research organization dedicated to innovative research and analysis that promotes global security, prosperity, and freedom. For more information about Hudson Institute, visit our website at www.hudson.org. Available Topic Expert(s): For information on the listed expert(s), click
appropriate link. Dennis Avery http://profnet.prnewswire.com/Subscriber/ExpertProfile.aspx?ei=52881 Dr. S. Fred Singer
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Neither Three Mile Island nor Chernobyl stopped China from building this nuclear power plant near Hangzhou in the 1980s. The country wants to build 27 more reactors by 2020. Some environmentalists say the plan makes sense because it would mean less reliance on coal and fewer emissions tied to global warming.
By Miguel LlanosReporter
msnbc.com
updated 7/7/2005 2:54:13 PM ET
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When it comes to global warming, President Bush's refusal to endorse mandatory action means he is largely isolated on the world stage. But when the curtain rose at the Group of Eight summit on Wednesday, he was poised to tout a climate strategy shared by some peers, and more surprisingly, by a few environmentalists: nuclear power.Nuclear power's downsides are well known: the potential for meltdowns, the question of how to safely store radioactive waste and the dangers of plutonium reaching terrorists' hands.But Bush, as well as British Prime Minister Tony Blair, host of the G8 summit, has been stressing a positive quality of nuclear power: the fact that it doesn't burn fossil fuel and therefore produces no carbon dioxide emissions, a key greenhouse gas that many scientists tie to global warming."It's time for this country to start building nuclear power plants again," the president said in a televised appearance in June at the Calvert Cliffs nuclear plant in Maryland. Nuclear power still produces 20 percent of the total U.S. electricity, but the Nuclear Regulatory Commission estimates that 100 new reactors would be needed over 20 years just to maintain that share."Nuclear power is one of America's safest sources of energy," Bush added, all "without producing a single pound of air pollution and greenhouse gases.The president has made similar pitches in recent months, and the message appears to be getting some traction."The growing pressure to confront global warming and reduce greenhouse gas emissions has breathed new life into zero-emissions nuclear power like nothing else," says Dan Esty, director of the Yale Center for Environmental
Law and Policy, which commissions an annual survey on Americans' energy attitudes.
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Now, even some environmentalists are breaking the ranks that formed after the partial meltdown at Three Mile Island in 1979 and the Chernobyl disaster in 1986. They say that the warming threat is so serious and so widespread that nuclear power should be reconsidered.A few venture even further, saying it's time to ramp up nuclear power.Ex-hippie fuels debate Stewart Brand, a one-time hippie and founder of the Whole Earth Catalog, stirred the pot with his "Environmental Heresies" essay in the May issue of Technology Review magazine."The only technology ready to fill the gap and stop carbon dioxide loading of the atmosphere is nuclear power," he wrote.Energy conservation and renewable energy are "still key" strategies, Brand told MSNBC.com. "The only issue is that it's not really enough."Mainstream environmentalists "treat nuclear as if it is a trade-off against conservation" — use less energy and nuclear won't be needed, he said."But it's really a trade-off against burning coal," Brand said. By ramping up nuclear, he said, nations can phase out coal, which is the dirtiest fossil fuel and causes hundreds of premature deaths each year in the United States alone.China, which relies on coal, understands that, Brand said, and plans to build 27 nuclear reactors by 2020."You do move ahead with what you've got and not wait. The time to reduce CO2 loading was 10 years ago," he said.Brand's position was partly inspired by other environmentalists who earlier went public in support of nuclear energy. They include Greenpeace cofounder Patrick Moore; James Lovelock, creator of the Gaia hypothesis, which views Earth as a self-regulating organism; and Hugh Montefiore, a former Anglican bishop in Britain who was asked to resign his longtime board seat at Friends of the Earth when he published his position last October.
Moore, who left Greenpeace over strategy differences a decade ago, told the House Energy and Resources Subcommittee last April that nuclear power's "benefits far outweigh the risks.""If the U.S. is to meet its ever-increasing demands for energy while reducing the threat of climate change and reliance on overseas oil, then the American nuclear industry must be revitalized and permitted to grow," he said.
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The 'maybe some day' camp Still other environmentalists, while not embracing nuclear power, are saying it could some day be a viable option — if safety issues can be resolved and steps are taken to ensure that plutonium produced as a byproduct from the process doesn't end up in the hands of terrorists."The problem of global warming is so serious that we must thoroughly consider every low-carbon option for producing power," the group Environmental Defense says on its Web site.The Natural Resources Defense Council has a similar position. "These problems" — safeguarding plutonium,reactor safety and nuclear waste disposal — "need to be solved before expanding our commitment to nuclear power," Thomas Cochran, head of the group's nuclear program, told Western governors last year.And Jonathan Lash, president of the World Resources Institute, has gone on the record saying: "I don't believe we should a priori exclude any viable alternative" for reducing greenhouse gas emissions, "including safe nuclear power, provided we address issues of waste disposal and security."New reactors safer Jim MacKenzie, a climate researcher at the institute and a physicist by training, says that a new design known as the pebble-bed reactor is "substantially safer" than existing reactors and "basically meltdown proof."But he also sees significant obstacles, starting with what he calls a "culture" at the U.S. Nuclear Regulatory Commission that favors the existing reactor designs. And he feels the industry is more focused on getting U.S. government subsidies than on addressing the nuclear waste and proliferation concerns.MacKenzie favors fostering a mix of greater efficiency and clean energy resources, not building dozens of nuclear plants.
The 'no way' activists Still other environmentalists refuse to entertain the nuclear notion at all, and took a public stand in June as the Senate debated bipartisan legislation to curb greenhouse gas emissions in part by providing incentives for nuclear and other low-carbon energy sources.“While we are committed to tackling the challenge of global warming, we flatly reject the argument that increased investment in nuclear capacity is an acceptable or necessary solution," the coalition led by Greenpeace, the Sierra Club and U.S. PIRG said in a statement. "Instead we can significantly reduce global warming pollution and save consumers money by increasing energy efficiency and shifting to clean renewable sources of energy.”That legislation, championed by Sens. John McCain, R-Ariz., and Joe Lieberman, D-Conn., died for other reasons but it reflected a move by some opposition Democrats to push the nuclear ball forward.Joining Lieberman, for example, were New Mexico Sen. Jeff Bingaman, the senior Democrat on the Senate Energy Committee, and Delaware Sen. Tom Carper.David Hamilton, the Sierra Club's global warming director, said he suspected nuclear advocates were testing whether some environmental groups would accept the financial incentives "as some kind of price to pay for moving global warming legislation forward."
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That didn't happen, with even the maybe-some-day camp saying subsidies don't make sense.Lash, the World Resources Institute president who left the nuclear option on the table, emphasized that "subsidizing a mature technology like nuclear power makes about as much sense as subsidizing Mr. Trump to build another tower."Opinion polls and smart money Where do Americans stand on all this?A Gallup survey in March 2005 found 54 percent were strongly or somewhat in favor of nuclear power. That's up from 48 percent in 2001 and down from 57 percent in 1994.
BibliographyDo you believe that humans caused global warming?? (n.d.). Retrieved September 23, 2010, from Global Warming Cause: http://www.globalwarmingcause.net/2010/08/07/do-you-believe-that-humans-caused-global-warming/
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