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Kudos
to John L. Daly, who has written a very interesting study of ice at the
North Pole. Global Warmists are once again observing cyclical changes
and declaring them "proof" of the dire effects of global warming.
Among
the interesting pictures posted to this site is this one from 1987,
when we were supposed to be worried about global cooling (above).
This was not exactly a harbinger of global warming, as this picture of unbroken ice at the North Pole three years later attests:
ABOVE: USS Hawkbill at the North Pole, Spring 1999. (US Navy Photo)
Daly explores the various factors influencing ice at the North Pole. It is accessible to laymen like me. His conclusions:
...both
the extent and thickness of Arctic sea ice is certainly subject to
variation. But it would be a mistake to assume that a brief period
during which the Arctic is in a thinning cycle is anything more than
that - a cycle. We know from past history that it has been subject to
earlier retreats as suggested by the opening quote from 1817.
Part
of the problem lay in the fact that useful data on ice extent and
thickness only dates from the 1950s, yet our temperature record from
Jan Mayen Island at the edge of the Arctic shows that the Arctic was
warmer during the 1930s than it was during the 1990s. Unfortunately
there is no comprehensive ice data from the 1930s. Instead such data
begins in the late 1950s, at a time when the Arctic was entering into
the grip of a known cold spell. As that cold period ended, it is hardly
surprising to find thinner ice during the latter warmer period. [....]
The
limits on the thickness of Arctic ice are determined by how low the air
temperature can get, and on how warm and fast-moving the subsurface
water is. Air temperatures measured in the Arctic region show no recent
warming, thus discounting the possibility that recent thinning of ice
could be caused by atmospheric warming above the ice. Rather, the
thinning of ice in the 1990s is clearly associated with a warming of
the sub-surface ocean, as shown by the SCICEX data, caused in whole or
in part by the strong NAO [North Atlantic Oscillation -- ocean current
change] increasing the flow rate of Atlantic water into the Arctic
Ocean.
There is nothing in the data to suggest anything but natural cycles at work.
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