Global warming puts Arctic on thin Ice
Answers to questions about the Arctic's shrinking ice cap and its
global significance.
Why are global warming specialists watching the Arctic so closely?
What kinds of changes are taking place in the Arctic now?
How does this dramatic ice melt affect the Arctic?
Will Arctic ice melt have any effects beyond the polar region? Can we
do anything to stop global warming?
Q: Why are global warming specialists watching the Arctic so closely?
A: The Arctic is global warming's canary in the coal mine. It's a
highly sensitive region, and it's being profoundly affected by the
changing climate. Most scientists view what's happening now in the
Arctic as a harbinger of things to come.
Q: What kinds of changes are taking place in the Arctic now?
A: Average temperatures in the Arctic region are rising twice as fast
as they are elsewhere in the world. Arctic ice is getting thinner,
melting and rupturing. For example, the largest single block of ice in
the Arctic, the Ward Hunt Ice Shelf, had been around for 3,000 years
before it started cracking in 2000. Within two years it had split all
the way through and is now breaking into pieces.
The polar ice cap as a whole is shrinking. Images from NASA
satellites show that the area of permanent ice cover is contracting at a
rate of 9 percent each decade. If this trend continues, summers in the
Arctic could become ice-free by the end of the century.
Q: How does this dramatic ice melt affect the Arctic?
A: The melting of once-permanent ice is already affecting native
people, wildlife and plants. When the Ward Hunt Ice Shelf splintered,
the rare freshwater lake it enclosed, along with its unique ecosystem,
drained into the ocean. Polar bears, whales, walrus and seals are
changing their feeding and migration patterns, making it harder for
native people to hunt them. And along Arctic coastlines, entire villages
will be uprooted because they're in danger of being swamped. The native
people of the Arctic view global warming as a threat to their cultural
identity and their very survival.
Q: Will Arctic ice melt have any effects beyond the polar region?
A: Yes - the contraction of the Arctic ice cap is accelerating global
warming. Snow and ice usually form a protective, cooling layer over the
Arctic. When that covering melts, the earth absorbs more sunlight and
gets hotter. And the latest scientific data confirm the far-reaching
effects of climbing global temperatures.
Rising temperatures are already affecting Alaska, where the spruce
bark beetle is breeding faster in the warmer weather. These pests now
sneak in an extra generation each year. From 1993 to 2003, they chewed
up 3.4 million acres of Alaskan forest.
Melting glaciers and land-based ice sheets also contribute to rising
sea levels, threatening low-lying areas around the globe with beach
erosion, coastal flooding, and contamination of freshwater supplies.
(Sea level is not affected when floating sea ice melts.) At particular
risk are island nations like the Maldives; over half of that nation's
populated islands lie less than 6 feet above sea level.
Even major cities like Shanghai and Lagos would face similar
problems, as they also lie just six feet above present water levels.
Rising seas would severely impact the United States as well.
Scientists project as much as a 3-foot sea-level rise by 2100. According
to a 2001 U.S. Environmental Protection Agency study, this increase
would inundate some 22,400 square miles of land along the Atlantic and
Gulf coasts of the United States, primarily in Louisiana, Texas, Florida
and North Carolina.
A warmer Arctic will also affect weather patterns and thus food
production around the world. Wheat farming in Kansas, for example, would
be profoundly affected by the loss of ice cover in the Arctic. According
to a NASA Goddard Institute of Space Studies computer model, Kansas
would be 4 degrees warmer in the winter without Arctic ice, which
normally creates cold air masses that frequently slide southward into
the United States. Warmer winters are bad news for wheat farmers, who
need freezing temperatures to grow winter wheat. And in summer, warmer
days would rob Kansas soil of 10 percent of its moisture, drying out
valuable cropland.
Q: Can we do anything to stop global warming?
A: Yes. When we burn fossil fuels - oil, coal and gas - to generate
electricity and power our vehicles, we produce the heat-trapping gases
that cause global warming. The more we burn, the faster churns the
engine of global climate change. Thus the most important thing we can do
is save energy.
And we can do it. Technologies exist today to make cars that run
cleaner and burn less gas, generate electricity from wind and sun,
modernize power plants, and build refrigerators, air conditioners and
whole buildings that use less power. As individuals, each of us can take
steps to save energy and fight global warming. Source: GOOGLE
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