7/20/15, "Increased Arctic sea ice volume after anomalously low melting in 2013," Nature Geoscience, Rachel L. Tilling, Andy Ridout, Andrew Shepherd, Duncan J. Wingham, doi:10.1038/ngeo2489
"Changes in Arctic sea ice volume affect regional heat and freshwater
budgets and patterns of atmospheric circulation at lower latitudes.
Despite a well-documented decline in summer Arctic sea ice extent by
about 40% since the late 1970s, it has been difficult to quantify trends
in sea ice volume because detailed thickness observations have been
lacking. Here we present an assessment of the changes in Northern
Hemisphere sea ice thickness and volume using five years of CryoSat-2
measurements. Between autumn 2010 and 2012, [two years] there was a 14% reduction in
Arctic sea ice volume, in keeping with the long-term decline in extent.
However, we observe 33% and 25% more ice in autumn 2013 and 2014,
respectively, relative to the 2010–2012 seasonal mean, which offset
earlier losses. This increase was caused by the retention of thick sea
ice northwest of Greenland during 2013 which, in turn, was associated
with a 5% drop in the number of days on which melting
occurred—conditions more typical of the late 1990s. In contrast,
springtime Arctic sea ice volume has remained stable. The sharp increase in sea ice volume after just one cool summer suggests that Arctic sea
ice may be more resilient than has been previously considered."
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Arctic will be ice-free by 1999, 2000, 2013, 2008, 2012, 2010, or 2015.
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