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Global Environmental Change
1
© 2011. Johns Hopkins UniversityExcept where attributed
Global Environmental ChangeChange
Brian S. Schwartz, MD, MS
1
Johns Hopkins Bloomberg School of Public HealthDepartmental of Environmental Health Sciences
July 29, 2011
Overview• Contexts• General definitions• General definitions• Key problems of GEC• For each
–Problem definition and scope –Some scientific evidence
2
Some scientific evidence–Health risks
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Sustainable Development"Meeting the needs of the
Contexts
Meeting the needs of the present generation without compromising the ability of future generations to meet their needs."
3
Gro Harlem Brundtland, World Commission on Environment and Development (Brundtland Report) [subsequently became Director-General of WHO], 1987
• Development: improving human condition in all its aspects (economic, sociopolitical, environmental)
*
environmental)• Sustainable development: by means and to
end points that are consistent with maintaining improved conditions indefinitely
• Sustainable well-being: sustainable development to achieve well-being where it is
4
p gabsent and putting the maintenance & expansion of well-being onto a sustainable basis where it is being provided unsustainably today
* Assistant to President Obama for Science & Technology, Director of White House Office of S & T Policy, & Co-Chair of President’s Council of Advisors on S & T
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Three Essential Pillars of Human Well-being
• Economic conditions and processes– Employment, income, wealth, markets, trade,
productive technologies
• Sociopolitical conditions and processes– Law & order, national & homeland security,
governance, justice, education, health care,
5
g jscience, culture, arts, liberty, privacy
• Environmental conditions and processes– Air, water, soils, mineral resources, biota,
nutrient cycles, climatic processes
The preservation and
enhancement of all three
are the core responsibilitiesare the core responsibilities
of societies
6
www.tahan.com
Corridors.conservation.orgTexasliberal.com
Nativeborncitizen.com
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Which of Three is Most Important?• Each is indispensable• Failure of any one can mean collapse of y p
the human enterprise• The three interact
– Economic systems cannot function without inputs from environmental system or stability provided by sociopolitical system
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– Societal stability cannot be maintained in the face of environmental disaster (even in the most prosperous countries)
• Social disruption may be the main outcome of concern
The world now faces unprecedented threats to these
three pillars – arising from resource limitations and uses – and thus to
human well-being.
This lecture is about trying to
8
y gconvince you about the existence and magnitude of some of those
threats …
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Environmental Signals at Global Level
• Atmospheric CO2
• Temperature
S l l
• Soil quality
• Pasture lands
• Sea levels
• Ecosystems
• Desertification
• Fisheries
• Coral reefs
• Storm intensity
• Forests
• Rangelands
• Glaciers
P l i
9
Co a ee s
• Water tables
• Biodiversity losses
• Soil quantity
• Polar ice caps
• Species losses
• Toxicants in air, water, soil
“We know from earlier
civilizations that the lead
indicators of economic
decline were environmental,
not economic. The trees went
first, then the soil, and finally
th i ili ti it lf T
10
the civilization itself. To
archeologists, the sequence
is all too familiar.”
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Peak oil and the
Threat #1. To all three pillars.
M. King Hubbert, 1903-1989. Geophysicist. • He made a startling prediction first made public in 1949
coming era of energy scarcity
11
He made a startling prediction, first made public in 1949, that the fossil fuel era would be of very short duration.
• In 1956 he predicted U.S. oil production would peak in 1970; he was scoffed at; he was exactly correct.
Our environment problem is mainly caused by energy; our energy problem is mainly because there is not enough environment.
The bell-shaped curve of production – Hubbert’s
Peak.
12
Hubbert’s original estimateScientific American, Energy and Power, 1971
Predicted world oil production would peak around 2000
It is a geologic reality that cannot be overcome with more drilling or new technology
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Note: Hubbert’s method worked
very well in 1956 to predict U.S.
Oil-producing Countries Past Peak
peak in 1970
13NGL = natural gas liquids
Monthly world oil production and prices, 2002–2010World oil production has stalled
Flat from 2005-10 while demand increased 2-5%/year
Data from US EIAFigure from Post Carbon Reader Ch 19
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
• Non-OPEC peaked in 2007• OPEC and thus world peaked in 1Q2008
WSJ Blogs, Environmental Capital, 5/4/09“Peak Oil: Global Oil Production’s Peaked”
(Raymond James, financial & energy investment services & analysis)
• OPEC, and thus world, peaked in 1Q2008“… contention rests on simple argument: OPEC oil
production … fell … as oil prices were above $100 per barrel, a sign of the ‘tyranny of geology’ …”
“… a paradigm shift of historic proportions.”
DailyDaily production vs.
price$
Oildrum.com
20031997
20052003
2004
2004
2005
2005 2005
2006
2005
2006
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2007
2006
20082009
2006 2009
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
OVERVIEW
GLOBAL HEALTH
FOOD
PUBLIC HEALTH DEPARTMENTS
URBAN FORM
CONFLICT
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COMMUNICATION
HEALTH CARE
URBAN FORM
Implications of Peak Oil Are Myriad• Economies – high correlation between per
capita GDP and per capita energy inputs• Food – our current system inefficiently converts
f il f l i t f dfossil fuels into food• Water – energy and water are inter-dependent• Population – remarkable parallel between use
of fossil fuels and population growth• Transportation – highly reliant on liquid fuels• Communities and built environment
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• Health – EMT, disaster preparedness and response, hospitals, pharmaceuticals, plastics
• War – very dependent on liquid fuels• Energy security – perhaps no such thing
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
“A Harsh Reality”• “Oil: Peaking some time in the
next three years, possibly already y y ypast peak
• Gas: Peaking some time in the next three to 13 years
• Coal: Peaking some time in the next 13 years
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next 13 years• Nuclear: Probably peaking some
time in the next 10 years, with lots of variables, but its use won’t increase substantially”
2008
Resource Scarcity• Petroleum – as already covered; and energy
scarcity minerals & materials scarcityy y
• Fresh water – impacted by climate change
• Agricultural land – China purchasing prime farmlands in Africa
• Phosphorus – US, China, Morocco possess most of the resource, already limiting exports
• Rare earth elements – renewable energy
• Soil – loss of top soils due to farm practices
20
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
The U S has the “wrong” built
Related Problem. Implications for all three pillars.
The U.S. has the wrong built environment. We heavily invested in
a model that likely will be greatly disruptive and disrupted in the 21st
Century and that is already affecting
21
Century, and that is already affecting public health in several ways.
I will tell you more about the built environment and public health on August 8th.
The Key Threats to Pillars from Global Environmental Change Are LINKED
• Global climate change (1)
• Stratospheric O3 depletion (2)
• Ecosystem destruction (3)
• Biodiversity & species loss (4)
… are caused by human behaviors & are a threat to health
1
2 3
… are caused by human behaviors & are a threat to health
22
WHO, 20064 3
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Climate
Threat #2. To all three pillars.
ClimateMagnifi.co.uk
Change
23Lal.cas.psu.edu
Unep.org
Asianet.fi
GALLUP POLL, April 21, 2008
National Journal, Oct. 2010: “The GOP is stampeding toward an absolutistNational Journal, Oct. 2010: The GOP is stampeding toward an absolutist rejection of climate science that appears unmatched among major political
parties around the globe.”
24
Rasmussen Reports, June 28-29, 2009: 41% of Americans opposed (37% in favor) to climate change and energy bill passed 219-212 along party lines in U.S. House of Representatives last month, now being considered in Senate.
National Republican Congressional Committee: “Democrats ongoing crusade against economic recovery.”
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Timelines• The planet is around 5B years old• Humans have been in settlements for
around 10,000 yearsaround 10,000 years• Industry and its hazards have been around
for approximately 200 years• Global climate change has been a concern
for around 30 years (first world climate conference in 1979, Kyoto Protocol 1997)
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conference in 1979, Kyoto Protocol 1997) • Hottest year on record 2005; 2010 tied;
2009 2nd; 2000-9 hottest decade on record
• This happened fast!
26
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Intergovernmental Panel on Climate Change, 2007
IPCC was created in 1998; 2007 was fourth full report
“Most of the observed increase in globally averaged temperatures
since the mid-20th century is very
p
27
likely due to the observed increase in anthropogenic
greenhouse gas concentrations.”
“… the pronouncements of the
IPCC do not represent mainstream
Tim Flannery, Australian mammologist, paleontologist, climate activist:
IPCC do not represent mainstream
science, nor even good science,
but lowest-common-denominator
science – and of course even that
is delivered at glacial speed. If the
28
IPCC says something, you had
better believe it – and then allow
for the likelihood that things are far
worse than it says they are.”
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
• Analysis of air bubbles in Antarctic ice cores• Similar data for CH4
and N O
A2
and N2O• Atmospheric CO2 has not exceeded 300 ppm in 800,000 years
B1
29US GCRP, 2009
Northern Hemisphere Temperatures, Past 1,000 Years
“Multiple indicators, same bottom line conclusion: consistent and unmistakable signal from the top of the
atmosphere to the bottom of the oceans”
30
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
A1F1
O
4°F / 2.2 °C
31
Observed and projected changes in global average temperature, three IPCC
scenarios, relative to 1960-79. A range of models predicts 2
to 11.5 °F.
Simulated and projected changes in amount of
precipitation in heaviest 5% of days, relative to 1960-79. More severe events are
coming.US GCRP, 2009
Momentum in Climate System and Lag Times: CO2, temperature,
and sea level continue to rise long after emissions are reduced
32IPCC
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
US GCRP, 2009
A1F1
World CO2 emissions, 2008, 40% higher than in 1990
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Actual emissions have been worse than even the most pessimistic IPCC projection (A1F1)
Examples of global emission pathways for cumulative CO2
emissions of 750 Gt, 2010-2050 (an amount with 67% probability of keeping global warming < 2°C).
If world population = 9B … this is
0.5T/person (US current = 20T/person )
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“An important consequence of the rapidly growing emissions rate … is that any delay in reaching the peak in emissions drastically increases the
required rapidity and depth of future emissions cuts.”
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Highlights• 2010 one of two warmest years on record (2005)• Weather extremes observed globally: hot, cold, wet, dry• Arctic continues to warm at twice rate of lower latitudes• Changes in ocean salinity patterns suggest increase in hydrologic cycle• Arctic sea ice extent third lowest on record since 1979 (Antarctic sea ice extent near maximum)• Greenland glaciers lost more mass than in any year on
d (10 )
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record (10y)• Greenland Ice Sheet lost record mass (since 1958), area & duration of melting largest since 1978• Permafrost temperatures 2°C warmer than 20-30y ago• 2010 is 20th straight year that alpine glaciers lost mass • CO2 increased 2.6 ppm, higher than 30y average rate
How do we know these changes are due to human activities?
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Detection and attribution research
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Studying Climate• Scientists study all this complexity using:
– Earth’s paleoclimate history: how did Earth respond to past changes, especially in response to boundary forcings*M d b i f li h i id i h
IPCC, 2001; Hansen, 2011
– Modern observations of climate change, coincident with rapidly-changing human-made & natural climate forcings
– Climate models and theory
• To project future climate:– Use historical observations – paleoclimatology– Use computer models
37
p• Current data to develop and validate model, then use
to predict future• Also use to understand perturbations – if current model
predicts current conditions well, perturb it to see how this might change outcomes of interest
* Boundary forcings are factors that affect Earth's energy balance (e.g., solar irradiance, ice sheet distribution, GHGs)
The Human Fingerprint
38US GCRP, 2009 Forcings in Watts/m2
A climate forcing is an imposed perturbation –
natural or human-made –of Earth's energy balance
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
“Catastrophic Climate Change”
• Sea level rise leading to
Stay < 2°C (3.8°F) increase, < 450 ppm CO2
gdisplacement of human populations (10’s – 100’s millions)
• Extinction of 50% of plant and animal species
39
p
• Regional climate change with large impacts on food production and hydrologic cycle
The Bad News About Climate Change• GHG emission trajectories over past 7 years:
worse than even the worst IPCC projections• In 2010, GHG emissions highest ever• Ocean absorption of CO2 has been declining• Ice sheet melting: much faster than predicted• Coral reef bleaching accelerating• Several tipping points in climate feedbacks
may soon be fully engaged – declining albedo, burning boreal forests Amazon dieback
40
burning boreal forests, Amazon dieback, melting permafrost, enhanced El Niño
• Growing consensus: 450 ppm will not be safe; need to get down to 350 ppm (now 390 ppm)
• To prevent < 2°C increase, emissions must start declining by 2016
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
2007 Climate models are not needed to calculate forcings – is about chemistry and physics.
Climate sensitivity (S) = equilibrium global surface temperature change (ΔTeq) in response to specified unit forcing afterin response to specified unit forcing after planet has come back to energy balance (S = ΔTeq/F).
Climate sensitivity depends upon climate feedbacks – physical processes that occur as climate changes in response to a forcing
41
as climate changes in response to a forcing – that can enhance or diminish climate response.
“Climate feedbacks are the core of the climate problem.” Hansen J, 2011
0.75°C per W/m2
3°C per 2xCO2
> 2°C per W/m2
> 8°C per 2xCO2
Examples of policy-relevant tipping points (those that could occur this century due to human activities)
Tipping point: critical threshold at which the future state of a system can be qualitatively altered by a small change in forcing.
+
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Others are not depicted (e.g., shallow
water corral reefs) Copenhagen Diagnosis
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Thawing permafrost above Arctic CircleMethane 23X CO2
“The Peril Below the Ice” – A Positive Feedback
43
ImpactsImpacts
442008
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
TemperatureSea level risePrecipitation
Health Agriculture Forest
IMPACTS ON …
Water resources
Coastalareas
Species & natural areas
45
Health Agriculture Forest resources areas areas
1. Global warming is unequivocal and primarily human-inducedprimarily human-induced
2. Climate changes are underway in the U.S. and are projected to grow
3. Widespread climate-related impacts are occurring now and are expected to increase
46
4. Climate change will stress water resources
5. Crop and livestock production will be increasingly challenged
2009
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
6. Coastal areas are at increasing risk from sea-level rise and storm surgesea-level rise and storm surge
7. Risks to human health will increase
8. Climate change will interact with many social and environmental stresses
9. Thresholds will be crossed, leading to
47
, glarge changes in climate and ecosystems
10.Future climate change and its impacts depend on choices made today
2009
Climate Change & Public Health
• More heat-related illness• Worsening air quality• Rising sea levels• Rising sea levels• More accidents and injuries from increased
flooding, storm surge, and extreme weather• Greater risk of infectious diseases• Threatened quantity & quality of water supplies• Threatened food supplies
St d t t ti l f ll d
48
• Stressed ecosystems, potential for collapse, and loss of ecosystem services
• Vulnerable populations• Environmental refugees, social disruption,
conflict
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Warmer Temperatures are Here
Heat-related morbidity and mortality – a direct health effect of climate change
Nature 2004: Summers like this in Europe willNature 2004: Summers like this in Europe will happen every other year by 2040
Summer 2003
35,000 dead49
Example: Climate on the Move – Changing Summers
Projections of summer average temperature and precipitation changes (mid = 2040 59 end = 2080 99)(mid = 2040-59, end = 2080-99)
Translates into considerably HOTTER and DRIER summers in both locations.
Many other similar regional impacts have been forecast: e g water levels
50
have been forecast: e.g., water levels in Great Lakes, coastal erosion, insect infestations, drought and flood risks
US GCRP, 2009
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Conrad Icefield and Glacier
Purcell MountainsBritish ColumbiaBritish Columbia
51
Melting, melting, melting …
Conrad Icefield and GlacierPurcell MountainsBritish Columbia
US GCRP, 2009
Cubic miles of glacier ice loss
52
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Retreating Margin of
Larsen B Ice Shelf, 1998-
2002
Red squares
indicate glacier
velocity
measurement
sites where speed
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sites where speed
increased up to 5X
faster in 12 mo
after 2002 ice
shelf breakup
54
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Rate of Greenland ice melting doubled from 1996-2005
Moulin(NASA photo)
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Arctic Sea Ice Arctic Climate Impact Assessment 11/2004Arctic Climate Impact Assessment 11/2004
Observed September 2003
2010-2030 2040-2060 2070-2090
----------------------------- PROJECTIONS----------------------------
Observed September 1979(first data)
56
Telegraph, UK, Apr 2009: “Scientists say Arctic could be ice-free within decade”
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
SoTC10: ARCTIC “Changes occurring faster than in most of rest of world. Trends in snow
cover duration, permafrost, & vegetation continued or accelerated.”
Updated to 2008 (Copenhagen Diagnosis)
57
2008
• IPCC: sea level projected to rise 7-23 in by 2100*
• Hansen: paleoclimate data t th t l l illsuggest that sea level will
rise > 20 ft (6 m) with 2°C
58
* … excludingfuture rapid dynamical
changes in ice flow & melting
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Rising Temperatures Worsen Air Pollution
Warmer temperatures
increase tropospheric
ozone formation
This has been linked to
asthma and
59
asthma and cardiovascular
disease hospitalizations
and deaths
DengueMalariaLyme disease
60
Some pests will thrive with change in climate: vector-borne disease risk
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Extreme EventsIPCC, 2007: Climate change will result in more
weather extremes – more heavy precipitation
events, floods, droughts, stronger hurricanes
(“climate chaos”)
• Regional extremes are very important to public health• More relevant to people; largest impact on communities
M diffi lt t d l t i bilit ll
61
• More difficult to model – greater variability on smaller scales & resolution of current models an issue• Much progress being made• Regional extremes attribution improving and projections are concerning
3-day average sea surface T°
Yellow
Katrina
Yellow, orange, and red areas are> 82° F (27.8° C, the T° needed for hurricanes to strengthen).
62
Min 26° C needed for hurricanes to form.
Epstein P. NEJM 2005; 353: 1433-6.
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
63
Hurricane projections to 2080 for 1% annual increases in CO2 levels
Just As the Challenges of Peak Oil Arrive, Climate Change Will Constrain Energy
ProductionUS GCRP, 2009:US GCRP, 2009:• Energy production is likely to be
constrained by rising temperatures and limited water supplies in many regions
• Energy production and delivery systems are exposed to sea-level rise and
t th t i l bl
64
extreme weather events in vulnerable regions
• Climate change is likely to affect some renewable energy sources (e.g., hydropower)
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
2008
• Water is needed to generate energy – very important and large quantities• Energy is needed to deliver water• These resources already limit the other –increasing examples• Switching from gasoline to electric vehicles or biofuels is a strategic decision to switch dependence from foreign oil to domestic water• Complex inter-connectedness – our theme
Linkages between
climate change, ecosystems,
My sick joke is that Eastern Australia had average rainfall for the last seven years. The first six were the driest six years in the record books, and the seventh
was feet deep in unprecedented floods. Such
Meeting needs for increased
yand food
production
“average” rainfall makes farming difficult.
Jeremy Grantham, GMO LLC, May 2011
66
Meeting needs for increased agricultural production has the
potential to increase global rates of biodiversity loss, climate change, & desertification.
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Summers in 2080-2100 Warmer than Warmest on Record
• Compared these temperatures to historical ones and their impacts on agricultureagriculture• Crop yields declined 20-50% at these temperatures• There will be food deficits in many parts of world• Tropics most susceptible• Most of world lives in these places
67
Using summer means (minimizes tails, thus under-estimating effect)
p• Adaptation may help, must start now
An Equation for DisasterForced migration of millions
+ Scarce resources, including energy
+ Shrinking economies
+ Already stressed infrastructures and
ecosystems
68
= Conflict• Wars over food, land, water, energy, environmental refugees?
• Each would have severe implications for population health.
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Environmental Conflicts
69TEEB, 2008
So, to review, and in summary …
70
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
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72
2009 dataUS: 5% population, 18% GHG emissions
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Deaths Attributed to Climate Change (selected outcomes only)
73Patz J, et al. Nature 2005; 438: 310-7.
WHO data for 2000; for cardiovascular diseases, diarrhea, malaria, inland and coastal flooding, and malnutrition.
In 2000 – 150,000 deaths
1995 Nobel Prize in
Chemistry
Stratospheric ozone depletion
74
depletion
Some slides from Pyle JA, Solomon S. IPCC WG1, obtained from http://arch.rivm.nl/env/int/ipcc/docs/SROCF/SBSTA22/01OzoneDepletion.pdf
July 19 2006
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
The Small BiosphereEarth diameter = 8,000 miles
Karman line (“edge of space”) = 62 miles
Biosphere (layer in which life can be found) = 8 miles
75Starryskies.com
Stratospheric ozone
Stratospheric Ozone• Most O3 in lower stratosphere, 15-25
km• Began accumulating 1-2B y ago • Began accumulating 1-2B y ago,
product of photosynthesis in aquatic algae & plants
• O2 is converted to O3 by high-energy photolytic action of UV radiation– Cl* from CFCs catalyze breakdown of O3
76
Cl from CFCs catalyze breakdown of O3
• Ozone layer blocks out all UV-C, 50% of UV-B, and small fraction UV-A*
• T1/2 for ozone regeneration: 3-4 y* Wavelengths: UVA 400 nm - 320 nm; UVB 320 nm - 290 nm; UVC 290 nm - 100 nm
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Chlorofluorocarbons (CFCs)• DuPont, first synthesized 1928• CFC-12 (R-12), DuPont trade name ( ),
Freon–Primary use as refrigerant in
residential refrigerators and mobile air conditioners
• CFC-11, 113, 114, 115 used in
77
production of other products–Foam rubber (blowing agents), rigid
insulating foam, solvents in electronics industry
CFCs and Ozone• 1974: Molina & Rowland, two American
scientists, hypothesize CFC role in Nature• 1978: U.S. bans use in spray cans9 8 U S ba s use sp ay ca s• 1983: Scandinavians propose global ban• 1985: Vienna Convention
–20 nations sign; declaration, not commitment–Precedent: multinational agreement on
78
environmental problem before clear scientific consensus
– In 1985, there was no evidence that CFCs actually damaged stratospheric ozone!
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Potential Effects of Ozone Depletion• Direct health effects
– SKIN: damage, cancer (10% loss, for 40 years, 300,000 new cases non-melanocytic skin cancer 5 000-9 000 new cases skin cancer, 5,000 9,000 new cases melanoma)
– EYE: cataracts, conjunctival epithelial thickening, ? retinal degeneration
– IMMUNE system: ? immunosuppression• Indirect effects
79
– Crop yields, forest growth– Phytoplankton reduction (under hole, 10% )– Positive feedback to global warming (GW
increases ozone depletion which enhances GW)
90°
60°
Regions of the world by latitude
30°
0°
30°
80
30
60°
90°
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Early Observations• 1985: British scientists – 40% loss of Antarctic ozone in late winter
and early spring• 1986-7: losses reported over both poles, late winter• 1988: inverse correlation measured between stratospheric CFC & O• 1988: inverse correlation measured between stratospheric CFC & O3
• 1980s: measured 50% increase in CFC levels
• 1988: new report, two important conclusions
– (1) Antarctic O3 hole caused by CFCs; and (2) O3 observed in North Temperate Zone
– Industrial opposition to CFC phase out disappeared; DuPont switches within 2 weeks
81
• 1980-92: at 30-50° N, O3 decreased 0.5%/y
• 1980s & 1990s: UV levels measured by satellite
– s of 5% per decade at 30° N and 30° S; 15% per decade at 55° S; 40% per decade over Antarctic; 10% per decade over Arctic
Measured
82
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
So, good news for the world. But not all the news is good.
NASA i l ti ld ith t t l Cl & B ll ti
2/3 of world total gone by 2065
NASA simulation – a world without controls on Cl & Br pollution
With controls, recovery was expected by 2050
83
“Amid the good news … lurk big questions about how long it will take … A decade ago, researchers projected … fully recover by 2050 … now … far more uncertainty. One … complicating factor … GHGs have altered atmospheric
conditions … since Montreal Protocol was signed, some of which speed up ozone recovery and some of which delay it.”
WMO & UNEP: > 700,000 excess cases 1980-2050 due
to ozone depletion
• MeBr pesticide still being used• MeBr pesticide still being used (was supposed to be phased out by 2005 in developed countries), after lobbying efforts• Cl- and Br-containing compounds in old air conditioners and fire-fighting systems expected to make it
84
g g sys e s e pec ed o a eto atmosphere as these break down• Br levels in stratosphere are higher than expected and than levels used in models
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
World Response Summarized• 1985: Vienna Convention• 1987: Montreal Protocol on Substances that Deplete the
Ozone Layer– 50% phase out of CFCs by 199850% phase out of CFCs by 1998
• 1990: London Revisions– Added new compounds, financial mechanisms for aiding
developing countries, added new control measures• 1992: Copenhagen Amendment
– Added HCFCs, HBFCs, and MeBr• 1997: Montreal Amendment
– Licensing systems for control & monitoring of substances
85
Licensing systems for control & monitoring of substances under agreements
• 1999: Beijing Amendment– New compounds, new control measures, new restrictions
on trade
• Virtually all countries have ratified these treaties
Compare & ContrastOzone Depletion & Climate Change
• Both are global in scale• Both pose significant potential risks to • Both pose significant potential risks to
inhabitants of this planet, both direct and indirect
• Both with significant sources of uncertainty and natural variability
• Both required complex computer modeling h h d d bl
86
• Both have generated considerable, rancorous debate
• One was “solved” before scientific consensus• The other – the heated debate continues
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
EcosystemEcosystem destruction
87
Millennium Ecosystem Assessment
• 1400 experts from 95 countries S t 4 d ti l b l • Spent 4 years conducting a global inventory of the state of our ecosystems
• Quantifying the effect that human activities are having on them (and on the impacts of ecosystem changes for human well being)
88
human well-being)• Identifying information gaps • Making suggestions for the future • Results released April 2005
Global Environmental Change
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© 2011. Johns Hopkins UniversityExcept where attributed
Millennium Ecosystem Assessment Findings
• 60 per cent of the planet's ecosystem services are currently being degraded by human activities
• 20 per cent of the world's coral
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reefs have been lost
• 40 per cent of the planet's rivers have been fragmented
Human Activities that Degrade Ecosystems
• Runoff of pesticides, fertilizers, and animal wastes animal wastes
• Pollution of land, water, and air resources • Introduction of non-native species • Over-harvesting of fisheries • Destruction of wetlands
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• Erosion of soils • Deforestation • Urban sprawl • Ecosystem fragmentation
Ecological Society of America, 2000
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Ecosystem Impacts
• Deforestation• Coastal wetlands• Marine fisheries• Coral reefs• Desertification
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The coming era of energy, water, and food
scarcity
Example: Marine Fisheries• Over-harvesting• Destructive practices
• Ocean acidification• Pollution runoff from land• Warming oceans
2009
• Bottom trawlers with enormous nets• 20 lbs bykill for each lb catch• Up to 55% coral, 67% sponges destroyed in single drag
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Seafloor destruction plume
drag• Area larger than CA already destroyed by U.S. trawlers
Satellite view, Gulf of Mexico
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Ecosystem Services• Moderate weather extremes and impacts • Disperse seeds • Mitigate droughts and floods • Protection from ultraviolet rays
Ecological Society of America, 2000
• Cycle and move nutrients • Protect streams, rivers, & coasts from erosion • Detoxify and decompose wastes • Control agricultural pests • Maintain biodiversity
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• Generate & preserve soils & renew fertility • Contribute to climate stability • Purify air and water • Regulate disease carrying organisms • Pollinate crops and natural vegetation
Images: nybooks.com
20071921
The “Third Pole” – Greater Himalayas and Tibetan Plateau: the largest non-polar ice mass in the world
A critical ecosystem function: collect and store monsoon rains
Mount Everest & Main Rongbuk Glacier, Tibet Autonomous Region, China, 1921-2007
A critical ecosystem function: collect and store monsoon rains
Feeds ten major rivers in Asia: Yellow, Yangtze, Mekong, Salween, Irrawaddy, Brahmaputra, Ganges, Indus, Amu Darya, and Tarim
Total flow from glacier melt: Indus 50%, Tarim 50%, Yangtze 18%, Salween 9%
But melt waters can account for up to 70% of spring and fall flows for each
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Energy Climate Ecosystems
• Energy issues, climate change, and ecosystem issues are intricately ecosystem issues are intricately interlinked
• To date, our ecosystem issues have looked less severe because we have used cheap energy to o e come them
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overcome them• Climate change is now an
overarching set of challenges on top of all ecosystem issues
Biodiversity andBiodiversity and species loss
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© 2011. Johns Hopkins UniversityExcept where attributed
First sightedMauritius
c. 1580
RIPEXTINCTc. 1681
97The dodo bird
The first human-caused extinction
5 Mass Extinctions• Ordovician
– Cause: glaciation
• Devonian– 70% of all species
Mass extinction: Earth loses 75%
of species in geologically short
time interval– Cause: global cooling
• Permian– Largest extinction event – 96% of all marine species, 75% of
terrestrial families – Cause: Siberian volcanism & warming
• Triassic
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– ~25% of all families, many vertebrates – Cause: CO2, warming, acidification
• Cretaceous– Most famous – dinosaurs – 85% of all species– Cause: meteorite impact theory
remains the most probable
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The 6th Mass ExtinctionCaused by Humans
• >16,000 species currently threatened with extinction– 100 to 1,000 times the “normal” background
rate of species extinction– In last 500 y, 844 extinctions due to human
activity– Numbers of threatened species are increasing
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Numbers of threatened species are increasing
• Different from previous– No cataclysmic natural event– Caused by humans
4
1
23
100
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Mean Species Abundance
1970 Arose out of G8+5 environment ministers meeting in Potsdam,
FRG, May 2007
TEEB, 2008
Major continuing
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2050
(% of original land biodiversity)
impacts, with additional 11% average losses
2000-50, with > 20% in some biomes, especially
in Africa, India, China.
Convention on Biological Diversity
• Came from Earth Summit in 1992–U.S. signed 1993
• The variability among living organisms from all sources including terrestrial, marine, and other aquatic ecosystems and the ecological
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complexes of which they are part. This includes diversity within species, between species and of ecosystems (CBD, 2002).
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Key Messages• Biodiversity has many benefits for
humans
• Declines in biodiversity due to human activities over the past 50 y have been rapid and unprecedented in human history
• The main drivers of change are getting worse & are
likely to continue or accelerate
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e y to co t ue o acce e ate
• An unprecedented effort would be needed to
achieve (by 2010) a significant reduction in the rate
of biodiversity loss at all levels
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Examined combined effects of pollution, acidification, ocean warming over-fishing and hypoxia
The world’s ocean is at high risk of entering a phase of extinction of marine species unprecedented in human historyJune 2011
ocean warming, over-fishing, and hypoxia.
The panel concluded that:
• The combination of stressors … is creating conditions associated with every previous major extinction … in Earth’s history• The rate of degeneration … is far faster than … predicted
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The rate of degeneration … is far faster than … predicted • Many … negative impacts previously identified are greater than the worst predictions• … the first steps to globally significant extinction may have begun with a rise in the extinction threat to marine species such as reef-forming corals
Bleaching as coral expel algae
Coral reefs: 0.2% of ocean floor; 25% of ocean’s biodiversity; key source of protein for 500M people, protect coastal shores from weather & tsunamis
World Resources Institute: 75% of world’s reefs at riskGlobal Coral Read Monitoring Institute: 20% of world’s reefs lost
Warming seas, ocean acidification expected to put all world’s reefs at risk by 2050
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Parting WordsClimate change + energy scarcity: h h h h h fthe canvas on which the history of the 21st Century will be painted.*
Climate change is likely to be the predominant scientific, economic, political and moral issue of the 21st century. The
107* Adapted from Mark Lynas
fate of humanity and nature may depend upon early recognition and understanding of human-made effects on
Earth's climate.
James E. Hansen, NASA Goddard Institute for Space Studies, 2011
“The Perfect Storm”
The “wrong” built environment
Ecosystem & species declines
Geopolitics of Conflict
Responses OutcomesChallenges
The coming era of energy scarcity
Climate change Deficits
environmentspecies declines
Huge fossil fuel inputs into food
production
scarcity
Social upheaval
Competition over resources
Population morbidity
P l ti
Refugees
Other resource scarcity
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Population mortality
(Workable solutions) (Sustainability)
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We the undersigned, senior members of the world’s scientific community, hereby warn all humanity what lies
ahead A great change in ourahead. A great change in our stewardship of the earth and life on it is required if vast human misery is to be avoided and our global home on this
planet is not to be irretrievably
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planet is not to be irretrievably mutilated.
The World’s Scientists’ Warning to Humanity, 1992 (1,700 scientists signed, 104 Nobel laureates)
2006Australia, Saudi Arabia
Brazil1.9
Indonesia1.6 Pakistan
0.8
#1Total emissions
Nigeria0.6
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From 2002-2006, per capita emissions increased from 2.1 to 4.6MT/y in China.
World average increased by ~15%.
#1#2 Total emissions
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An Editorial• There is a lot we can do NOW with
technology … but not much happening• While we are waiting for political, g p ,
business, and public health leaders to act …
• … what can WE do now?• American behaviors are the biggest
cause of this problemh h ll d d b
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• The challenges presented today may be the most difficult humanity has ever faced
• The threats to human health and well-being are potentially catastrophic
Which future do you prefer?
Is this a false choice or real?
112Scientific American 2006
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Remember:
We have NOT EVEN
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NOT EVEN TRIED YET