Saturday, September 22, 2007
Kids for Cubs Club - coming soon!
Human kids helping polar kids, a new club idea we are working on... spreading awareness about the increasing tragedy surrounding global warming, one small step at a time.
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Arctic Sea Ice Shrinks to Record Low, Scientists Say
By Alex Morales and Mathew Carr
Sept. 21 (Bloomberg) -- Arctic sea ice shrank to the smallest area on record this year, covering 22 percent less of the ocean than the previous low in September 2005, U.S. scientists said.
Sea ice covered 4.1 million square kilometers (1.6 million square miles) on Sept. 16, the National Snow and Ice Data Center in Boulder, Colorado said in a statement on its Web site, using a five-day rolling average. That's 1.2 million square kilometers less ice than the previous record -- or an area roughly the size of Texas and California combined.
The retreat of ice has added urgency to the debate on climate change, and prompted a scramble by countries including Russia and Denmark for ownership of the Arctic seabed and its mineral deposits. The decline also threatens to unbalance Arctic habitats, posing a danger to species including polar bears.
``If there is no summer sea ice, then there will be no ice- based Arctic ecosystem,'' Ben Stewart, a spokesman for Greenpeace U.K., said today in a telephone interview. ``It's the canary in the coalmine: the impacts of climate change seem to be happening faster than the scientists predicted a few years ago.''
This year's sea ice matched the 2005 record in August, with a month of melting left to go, an indication an ice-free North Pole may occur in coming years, Mark Serreze, a scientist at the center, said in an Aug. 17 interview. The melt opened up the Northwest Passage, a path between the Atlantic and Pacific long sought by mariners as a potential trade route.
Seabed Claims
``The Northwest Passage is still open but is starting to refreeze,'' the NSIDC said. ``The Northeast Passage along the coast of Siberia is still closed by a narrow band of sea ice.''
Russia, Canada, the U.S., Norway and Denmark all have territory in the Arctic Circle, and under the United Nations Law of the Sea, all have rights to the seabed within 200 (320 kilometers) miles of their shores.
Russian explorers on Aug. 2 planted a national flag on the seabed under the North Pole, saying that the underwater Lomonosov Ridge links Siberia to the seabed, enabling them to extend their claim. Denmark, which has rights to the Arctic because Greenland is a Danish territory, called the Russian action a ``joke,'' and Canada said the Russians are ``fooling'' themselves.
The United Nations Intergovernmental Panel on Climate Change this year said global warming is ``very likely'' caused by human activities, and that average temperatures in the Arctic are increasing at twice the global rate.
Ice Free Pole?
The warmth has led not only to the summer melting of southerly ice, but also to a decline in the so-called ``perennial'' sea ice that doesn't normally melt. Last September, the National Aeronautics and Space Administration said that a Texas-sized portion of perennial ice had been lost.
At current rates of melting, scientists are revising forward their predictions on when the Arctic may be ice-free in summer. Serreze said that the observed rate of decline was faster than any of the models indicated.
``If we were talking even two or three years ago, I'd have said the transition to an ice-free Arctic summer might be between 2070 and 2100,'' Serreze said in August. ``But what we're starting to see is that is rather optimistic, and an educated guess right now would be 2030. It's something that could be within our lifetime.''
The melting of sea-ice has little direct impact on sea levels because the ice is already resting on the water. The loss of ice cover does, however exacerbate global warming through a so-called feedback loop, said Serreze and Greenpeace's Stewart.
``The exposed sea reflects less of the sun's heat than the ice, which feeds back into global warming,'' Stewart said.
Polar Bears
The long-term average minimum for sea ice extent after the northern hemisphere summer, based on data from 1979 to 2000, is 6.7 million square kilometers, according to the center. While the ice has an annual cycle, melting from March until mid- September, scientists have recorded a steady decline in the summer minimum since the beginning of the satellite data series in late 1978.
The melting poses a danger to polar bears, which rely on the ice as their hunting ground. Future reductions in ice could result in a loss of two-thirds of all polar bears, the U.S. Geological Survey said earlier this month in a report. The survey group forecast that by mid-century, 42 percent of the species' ``optimal'' habitat will be lost during summers.
The polar bear, whose latin name is Ursus maritimus, last year was rated as a threatened species on the World Conservation Union's Red List. The union said at the time that the bears ``are set to become one of the most notable casualties of global warming.'' The U.S. Fish and Wildlife Service said in December that it will work to determine whether polar bears should be categorized as ``threatened'' under the Endangered Species Act.
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