Newly released images from NASA and the National Snow and Ice Data Center show that the Arctic’s melt season has lengthened significantly over the past few decades.
The melting season—i.e. the length of time in which continuous melting occurs—has increased on average by 6.4 days for every decade between 1979 and 2007. Around the lower-latitude edges of the ice pack, however, this lengthening was far above the average.
According to NASA, researchers collect this data by using satellite observations of the microwave energy radiated from the Arctic ice, which reveals the appearance of even small amounts of melt water.
According to the press release: “This trio of images shows changes between 1979 and 2007 in the average date of melt onset in the spring (left), the first autumn freeze (center), and the total average increase in the length of the Arctic sea ice melt season. The color scales show the trends in days per decade. Red indicates trends consistent with warming: earlier melt onset, later freezes, and longer total melt season. White indicates little or no change.” Image courtesy of NASA.
According to the press release: “The graph […] illustrates how the length of the melt season varies significantly from year to year, but the long-term trend is clear.” Image courtesy of NASA.
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