1
Since 1850: Ref: IPCC-AR4
Temperature is up 1°C (1.8°F) and climbing steeply
Sea Level is up 2 cm (5”) and climbing fast (due to melting ice & snow)
NH Snow Cover is down 3,000,000 km2 and dropping
1958-76 1993-97
In 30 years Arctic Sea Ice has thinned by half.Barry Huebert, [email protected]
The Climate-Change Skeptics are Wrong: Man-Caused Climate Change is Well
Underway … And Very, Very Scary!
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Before the Industrial Revolution, CO2, CH4, and N2Oin the air hardly changed. Now all these greenhouse gases are skyrocketing
due to human activities.
The Earth is in Energy Balance: The same amount of energy is absorbed from the Sun and lost as
Infrared radiation.Greenhouse gases prevent the escape of some IR,
causing the Earth to warm up.Warming is not the only effect, though: rain changes, storms intensify, and ice melts.
1 Light colored ice reflects back the Sun’s energy efficiently.2 Exposed land is darker and absorbs more energy; warming.3 As the ice melts, more land is exposed. This absorbs more heat, melting more ice, and causing further warming.4 The altitude of the melting ice is reduced so it becomes harder for new ice to form (esp for Greenland).
Positive Feedback: Some Warming Causes More Warming!
Ice-melt Positive Feedback can cause a Runaway Warming, by darkening
originally-light surfaces.Indeed, ice is melting MUCH faster
than glaciologists had forecast: Since the inhabited Earth has never experienced these conditions, there
were no observations of rapidly melting ice on which to base predictions.
Melt descending
into a moulin, a vertical shaft carrying water to the base of the Greenland
ice sheet.
4
Everything you consume* uses fossil fuels in its manufacture, packaging, and transport, producing CO2 at every step.
What Can you DO?Conserve EverythingReduce WasteRecycle everything you canEducate family and friends about the need for their helpCampaign hard for Green politiciansWrite letters to policymakers demanding fuel economy standardsUse renewable energy every time you can (solar hot water)Turn off lights & switch to fluorescentsMinimize air-conditioningUse just one towel in restroomsCarry groceries in reusable cloth bagsUse feet, bicycles, and public transit rather than automobilesGive dirty looks to people driving SUVs and Hummers to the mallTake shorter, cooler showersDon’t live alone
The nature of our future environment depends strongly on which “scenario” forecasters use.
The scenarios differ only in the extent of society’s effort to conserve and reduce fossil-fuel use.
Oil and power companies are not to blame for climate change.
You are!! Not “us!”
YOUR behavior will determine how badly Earth is damaged.
