Research and Application News
Arctic sea ice summertime minimum is fourth lowest on record
15 September 2015
According to a NASA analysis of satellite data, the 2015 Arctic sea ice minimum extent is the fourth lowest on record since observations from space began.
The analysis by NASA and the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado at Boulder showed the annual minimum extent was 1.70 million square miles (4.41 million square kilometres) on 11 September. This year's minimum is 699,000 square miles (1.81 million square kilometres) lower than the 1981-2010 average.
Arctic sea ice cover, made of frozen seawater that floats on top of the ocean, helps regulate the planet's temperature by reflecting solar energy back to space. The sea ice cap grows and shrinks cyclically with the seasons. Its minimum summertime extent, which occurs at the end of the melt season, has been decreasing since the late 1970s in response to warming temperatures.
In some recent years, low sea-ice minimum extent has been at least in part exacerbated by meteorological factors, but that was not the case this year.
Image credit: NASA/Goddard Scientific Visualization Studio - 2015 Arctic sea ice extent