Researchers from the Centre for Polar Observation and Modelling at University College of London used new data from the European Space Agency's CryoSat-2 satellite spanning 2010 to 2012, and data from NASA's ICESat satellite from 2003 to 2008 to estimate the volume of sea ice in the Arctic.
The team, led by Professor Seymour Laxon (UCL Earth Sciences), found that from 2003 to 2008, autumn volumes of ice averaged 11,900 km3. But from 2010 to 2012, the average volume had dropped to 7600 km3 – a decline of 4300 km3.
Average ice volumes in winter from 2003 to 2008 was 16,300 km3, dropping to 14,800 km3 between 2010 and 2012 – a difference of 1500 km3.
''The data reveals that thick sea ice has disappeared from a region to the north of Greenland, the Canadian Archipelago, and to the northeast of Svalbard,'' said Dr Katharine Giles (UCL Earth Sciences), who co-authored the report, published online in Geophysical Research Letters.
The findings confirm the continuing decline in Arctic sea-ice volume simulated by the Pan-Arctic Ice-Ocean Modelling and Assimilation System (PIOMAS), which estimates the volume of Arctic sea ice using data from submarine, mooring, and satellite observations.
Other satellites have already shown drops in the area covered by Arctic sea ice as the climate has warmed. Indeed, sea-ice extent reached a record minimum in September 2012. But CryoSat-2, launched in April 2010, differs in that it lets scientists estimate the volume of sea ice – a much more accurate indicator of the changes taking place in the Arctic.