Since the draft of latest +1000 pages US Climate Assessment completely ignores volume as a dimension of Arctic sea ice - probably assuming constant thickness during satellite era - I'll start here a series of findings to give evidence sea ice volume is not an unknown thing to science.
To be fair, the search term 'sea ice thickness' appears once in Chapter 12, Tribal, Indigenous, and Native Lands and Resources
Scientists across the Arctic have documented regional warming over the past few decades at twice the global rate, and indigenous Arctic communities have been observing the changes in their daily lives. This warming is accompanied by significant reductions in sea ice thickness and extent, increased permafrost thaw, more extreme weather and severe storms, changes in seasonal ice melt/freeze of lakes and rivers, water temperature, flooding patterns, erosion, and snowfall timing and type
Later this spring the series will result in a comment to the draft and hopefully the key message with a projection of an ice free Arctic earliest in the middle of the century got revised.
Here is the first part of the series, a paper presented for discussion earlier this week, written by V. A. Alexeev, V. V. Ivanov, R. Kwok and L. H. Smedsrud and titled: North Atlantic warming and declining volume of arctic sea ice, [full text] The article tries to estimate the eﬀect of the recent North Atlantic warming on the ice melting processes happening at the outlet of the Arctic Ocean near Fram Strait, Svalbard and Franz Joseph
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