Eos, Transactions American Geophysical Union

Reductions in Arctic sea ice cover no longer limited to summer



Summer sea ice in the Arctic has shown a significant downward trend of 8% per decade since the late 1970s, leading to a reduction of approximately 20% in sea ice extent in September (when the annual minimum occurs) (Stroeve et al., 2005). The past three summers (2002–2004) have been among the lowest on record, and 2002 was the extreme minimum. Despite decreasing summer extents, the sea ice extent has typically rebounded to near-normal levels during the winter season, yielding an annual average trend of only −3%. This is not surprising since as temperatures drop below freezing, sea ice quickly forms.