Arctic sea ice appears to have reached a record low wintertime maximum extent for the second year in a row, according to scientists at the National Snow and Ice Data Center and NASA. This short animation shows the Arctic sea ice freeze cycle from the last summertime minimum extent to March 24, when it reached its wintertime maximum extent: at 5.607 million square miles, it is the lowest maximum extent in the satellite record.
Arctic sea ice decline is the sea ice loss observed in recent decades in the Arctic Ocean. The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report states that greenhouse gas forcing is largely, but not wholly, responsible for the decline in Arctic sea ice extent. A study from 2011 found the decline to be “faster than forecasted” by model simulations. The IPCC Fifth Assessment Report concluded with high confidence that sea ice continues to decrease in extent, and that there is robust evidence for the downward trend in Arctic summer sea ice extent since 1979. It has been established that the region is at its warmest for at least 40,000 years and the Arctic-wide melt season has lengthened at a rate of 5 days per decade (from 1979 to 2013), dominated by a later autumn freezeup. Sea ice changes have been identified as a mechanism for polar amplification.
Credit: NASA Goddard’s Scientific Visualization Studio/C. Starr