Arctic sea ice shrinks to its lowest in 3 decades

Sea ice covering the Arctic Ocean has shrunk to its lowest size ever in 32 years since regular observations of the polar cap via satellites, US scientists said. US space agency NASA and the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado said, “The extent of Arctic sea ice on August 26, as measured by the Special Sensor Microwave/Imager on the US Defense Meteorological Satellite Program spacecraft was 1.58 million square miles (4.10 million square kilometers), or 27,000 square miles (70,000 square kilometers) below the September 18, 2007, daily extent of 1.61 million square miles (4.17 million square kilometers). The sea ice cap naturally grows during the cold Arctic winters and shrinks when temperatures climb in the spring and summer. But over the last three decades, satellites have observed a 13% decline per decade in the minimum summertime extent of the sea ice. The thickness of the sea ice cover also continues to decline. NASA’s Goddard Space Flight Center in Greenbelt Senior Research Scientist Joey Comiso, said, “The persistent loss of perennial ice cover – ice that survives the melt season – led to this year’s record summertime retreat. Unlike 2007, temperatures were not unusually warm in the Arctic this summer.” The new record was reached before the end of the melt season in the Arctic, which usually takes place in mid- to late-September. Scientists expect to see an even larger loss of sea ice in the coming weeks. “In 2007, it was actually much warmer,” Comiso said. “We are losing the thick component of the ice cover. And if you lose the thick component of the ice cover, the ice in the summer becomes very vulnerable.” “By itself it’s just a number, and occasionally records are going to get set,” NSIDC research scientist Walt Meier said about the new record. “But in the context of what’s happened in the last several years and throughout the satellite record, it’s an indication that the Arctic sea ice cover is fundamentally changing.”