Re: [asa] Arctic sea ice and global warming

> Janice's "argument" is once again one of fallacy. The reason polar
> bears are thriving since the 1970's is because of hunting agreements.
> However, the fact that their habitats are being destroyed is a real
> phenomenon.

Actually, the main flaw in the quoted article is the assumption that a
single large block of ice this year makes up for the long-term loss of
ice. Ironically, the released block is likely to be symptomatic of
general melting (though it might be part of the ordinary process-not
enough data in the quotation to tell).

Polar bears get much of their food by catching seals at their
breathing holes when the ocean is iced over. This is why a lack of
sea ice is a problem for the bears. This is also why my brother had
to always be with someone with a gun when he was doing field work near
Churchill, Manitoba, during the summer-the polar bears are bored and
hungry when the ice is gone. A big chunk of ice floating out to sea
does not solve the problem; in fact, ice attached to shore is better
for the bears (no nearby open area for the seals to hang out in).

As far as the seals are concerned, problems for the bears are a good
thing, but other aspects of their lifestyle will be negatively
impacted. In particular, the Arctic is undergoing significant
freshening, due not only to melting ice in the immediate area but
greatly increased river flows, especially in Asia. This in turn
affects global ocean current patterns and thus global climate, as well
as potentially affecting what can live in the Arctic Ocean, which has
rather limited connection with the outside ocean and seems to have
become a non-marine lake in part of the Eocene.

-- 
Dr. David Campbell
425 Scientific Collections
University of Alabama
"I think of my happy condition, surrounded by acres of clams"
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