Arctic sea ice grows and declines seasonally, ranging from an average minimum extent in September of 2.5 million square miles  to an average winter maximum extent of 5.9 million square miles  in March. This March, instruments on NASA’s Aqua satellite and National Oceanic and Atmospheric Administration (NOAA) and the United States Defense Department satellites showed the maximum sea ice extent slightly increased by 3.9 percent over that of the previous three years, but it is still below the long-term average by 2.2 percent. Increases in ice extent occurred in areas where surface temperatures were colder than the historical averages. At the same time, as a result of the export of ice from the Arctic, the area of perennial ice decreased to an all-time minimum.
Arctic sea ice grows and declines seasonally, ranging from an average minimum extent in September of 2.5 million square miles (6.5 million squeare km) to an average winter maximum extent of 5.9 million square miles (15.3 million square km) in March. This March, instruments on NASA’s Aqua satellite and National Oceanic and Atmospheric Administration (NOAA) and the United States Defense Department satellites showed the maximum sea ice extent slightly increased by 3.9 percent over that of the previous three years, but it is still below the long-term average by 2.2 percent. Increases in ice extent occurred in areas where surface temperatures were colder than the historical averages. At the same time, as a result of the export of ice from the Arctic, the area of perennial ice decreased to an all-time minimum.
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(6.5 million squeare km)
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(15.3 million square km)