One of the references in the Arctic sea ice report card was "
The Thinning of Arctic Sea Ice, 1988-2003: Have We Passed a Tipping
Point?
R. W. LINDSAY AND J. ZHANG
A portion of the abstract reads:
Internal thermodynamic changes related to the positive ice-albedo
feedback, not external forcing, dominate
the thinning processes over the last 16 yr. This feedback continues to
drive the thinning after the
climate indexes return to near-normal conditions in the late 1990s.
The late 1980s and early 1990s could be
considered a tipping point during which the ice-ocean system began to
enter a new era of thinning ice and
increasing summer open water because of positive feedbacks. It remains
to be seen if this era will persist or
if a sustained cooling period can reverse the processes.
It is important to note the manuscript was received 2 December 2004.
Since then, melt back has created a field of new ice and refreeze has
begun much later and at a much slower pace than the authors might have
imagined in 2004.
As their study said:
"Internal thermodynamic changes related to the positive ice-albedo
feedback, not external forcing, dominate the thinning processes over
the last 16 yr."
How could that internal dynamic mechanism be reversed with that
massive expanse of 'warm' Arctic Ocean slow to give up its heat? The
next melt season will begin with a great deal more new ice made
thinner because of the short refreeze time.
The tipping point has been passed. The total refreeze area might not
equal that of 2006. If it does, the average thickness will undoubtedly
be much thinner than 2006 (shorter refreeze period).
To borrow a line from Sonny Bono.............the heat goes on.
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