The Arctic Ocean’s ice cover has shrunk to the smallest size ever observed in the three decades NASA has monitored it, according to the U.S. agency.
The area of ocean covered by ice shrank to 1.58 million square miles (4.1 million square kilometers), or 27,000 square mile less than the 2007 previous record, the National Aeronautics and Space Administration and the U.S. National Snow and Ice Data Center in Boulder, Colorado, said today in a statement.
While the sea ice melts every summer before freezing again in September, the minimum summertime amount has declined 13 percent a decade for the past three decades, NASA said.
“The persistent loss of perennial ice cover -- ice that survives the melt season -- led to this year’s record summertime retreat,” Joey Comiso, senior research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said in the statement.
The increasing melt may be a harbinger of greater changes such as the release of methane compounds from frozen soils that could exacerbate warming, and a thaw of the Greenland ice sheet, which would contribute to rising sea levels, NASA’s top climate scientist, James Hansen, said in an e-mail interview earlier this month.