Climate science from the European Space AgencyAn international team of scientists working with data from the European Space Agency (ESA) Cryosat satellite (which can measure ice thickness using a high-resolution radar altimeter) has found that Arctic ice loss has been significant between 2003 and 2012, declining by 36% during autumns and 9% during winters. This is important because they are able to measure ice thickness, not just measure the sufrace covered by ice. Total ice loss might be more visible, but the ice getting progressively thinner is also problematic.
Satellite records show a constant downward trend in the area covered by Arctic sea ice during all seasons, but in particular in summer. The past six years have seen the lowest summer ice extent in three decades, reaching the lowest last September at about 3.61 million sq km. [...]
Since 2008, the Arctic has lost about 4300 cubic km of ice during the autumn period and about 1500 cubic km in winter. [...]
“Other satellites have already shown drops in the area covered by Arctic sea ice as the climate has warmed, but CryoSat allows scientists to estimate the volume of sea ice – a much more accurate indicator of the changes taking place in the Arctic,” added Tommaso Parrinello, CryoSat Mission Manager.
Caption for the image above: ICESat, CryoSat and PIOMAS sea ice thickness measurements in the Arctic. Figure (a) shows the 2003–07 average ICESat ice thickness for October/November and (b) the 2004–08 average for February/March. Figures (c) to (f) are measurements based on CryoSat data, for October/November 2010 (c), February/March 2011 (d), October/November 2011 (e) and February/March 2012 (f). The final two figures are based on PIOMAS measurements for October/November 2011 (g) and February/March 2012 (h).
You can see an animation here.