Q. Dear Twig: So scientists say that the Arctic ice cap is melting — getting smaller. Two questions: What do they say is the reason? And what do they say is going to happen to the polar bears?
A.: Scientists blame global climate change, also called global warming, for the North Pole ice cap shrinking.
A report called the Arctic Climate Impact Assessment says this: that "Earth's climate is changing, with the global temperature now rising at a rate unprecedented ["un-PRESS-uh-den-tid"; unheard-of] in the experience of modern human society. ... These climate changes are being experienced particularly intensely in the Arctic."
What's behind it?
Apparently Homo sapiens.
Most of the global warming of the past 50 years is due to human activities, the report says, "and there is new and strong evidence that in the Arctic much of the observed warming over this period is also due to human activities."
Next: Question 2, the polar-bear question.
Notes: Two groups teamed to carry out the Arctic Climate Impact Assessment: the Arctic Council and the International Arctic Science Committee. The 180 scientists who contributed to the effort (all of them called "well-recognized experts in their fields of study") came from 12 countries, including all of the Arctic countries. Some 200 additional scientists from 15 countries conducted a "rigorous and comprehensive" review of the findings. Read more at http://www.acia.uaf.edu/. Included are links to free downloads of the full 1,020-page scientific report; a 140-page "synthesis report"; and a 20-page highlights brochure.
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