Thomas Lifson
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.
....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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