In the summer of 2012, the floating cap of sea ice in the Arctic Ocean shrunk the smallest area ever recorded in the satellite era, which begins in the late 1970s. In fact, the ice cap melted to an extent less than half of what it was at the same time of year in 1979, making it one of the most dramatic and visible signs of climate change.

Arctic sea ice endures an annual shrink and swell cycle as temperatures change with the seasons. It typically reaches its smallest extent at the end of the summer. But lately scientists — including former NASA chief scientist and polar researcher Waleed Abdalati, now at the University of Colorado — have begun to talk more about the possibility of the ice cap melting completely in the summer in the coming decades.

So far, the 2013 melt rate is not matching 2012. But scientists don’t expect a consistent year after year loss; annual variations in air and ocean temperatures mean that the size of the sea ice cap will fluctuate year to year. But will it melt away one of these summers?

You can also find this graphic on NASA’s Climate 365 Tumblr page.


NASA Climate 365 project - a collaboration of the NASA Earth Science News Team, NASA Goddard and Jet Propulsion Laboratory communications teams, and NASA websites Earth Observatory and Global Climate Change.