Since 1850:
AR4
Ref: IPCC-
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
The Climate-Change Skeptics are Wrong:
Man-Caused Climate Change is Well
Underway … And Very, Very Scary!
In 30 years Arctic Sea Ice has thinned by half.
1
Barry Huebert, huebert@hawaii.edu
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:2rain
changes, storms intensify, and ice melts.
Positive Feedback: Some Warming Causes More Warming!
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).
Melt
descending
into a moulin,
a vertical shaft
carrying water
to the base of
the Greenland
ice sheet.
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.
Everything you consume* uses fossil fuels in its manufacture,
packaging, and transport, producing CO2 at every step.
What Can you DO?
Conserve Everything
Reduce Waste
Recycle everything you can
Educate family and friends about the need for their help
Campaign hard for Green politicians
Write letters to policymakers demanding fuel economy standards
Use renewable energy every time you can (solar hot water)
Turn off lights & switch to fluorescents
Minimize air-conditioning
Use just one towel in restrooms
Carry groceries in reusable cloth bags
Use feet, bicycles, and public transit rather than automobiles
Give dirty looks to people driving SUVs and Hummers to the mall
Take shorter, cooler showers
4
Don’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.
YOUR behavior
will determine
how badly Earth
is damaged.
Oil and power companies are not to blame for climate change.
You are!!
Not “us!”