The National Snow and Ice Data Center (NSIDC) has issued a preliminary announcement that Arctic sea ice reached its minimum extent for 2015 on September 11, and this was the fourth lowest in the satellite record.
On September 11, 2015, sea ice extent measured 4.41 million square kilometers (1.70 million square miles), the fourth lowest minimum since satellite records started at the end of the 1970s.
Sea ice extent ranked behind 2012 (lowest), 2007 (second lowest), and 2011 (third lowest). The nine lowest extents in the satellite era have all occurred in the last nine years as a result of climate change.
In the Antarctic, sea ice extent is average. This is in contrast to recent years when Antarctic winter extents reached record high levels.
Arctic sea ice extent will now begin its seasonal increase through autumn and winter.
NSIDC stressed that its announcement is preliminary. Changing winds or late-season melt could still reduce the Arctic ice extent, as happened in 2005 and 2010. NSIDC scientists will release a full analysis of the Arctic melt season, and discuss the Antarctic winter sea ice growth, in early October.
Details from NSIDC are available here
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WMO Global Cryosphere Watch website is available here