Arctic sea ice thinning at record rate     Arctic sea ice extent as seen by Envisat’s Advanced Synthetic Aperture Radar (ASAR) sensor during mid-September 2007 and mid-September 2008. The Arctic sea areas covered by ice in September 2008, but ice-free in September 2007, are visible in blue. The Arctic sea areas covered by ice in September 2007, but ice free in September 2008, are visible in dark brown. The Arctic sea covered by ice both in September 2007 and September 2008 are visible in light brown.   Circumpolar average winter season (October to March) ice thickness anomalies (from Katharine A. Giles, Seymour W. Laxon and Andy L. Ridout, Circumpolar thinning of Arctic sea ice following the 2007 record ice extent minimum, Geophysical Research Letters). Release date: 28 February 2012