Atmosphere Summary

Section Coordinator: James E. Overland

NOAA Pacific Marine Environmental Laboratory, Seattle, WA, USA

November 10, 2011

In 2011, annual near-surface air temperatures over much of the ocean were approximately +1.5 °C greater than the 1981-2010 baseline period and land temperatures were also above their baseline values. This continued a decade-long warm-bias of the Arctic relative to mid-latitudes. The wintertime increase and the summertime decrease in cloudiness resulted in greater energy flux to the surface, potentially contributing to the near record low sea ice extent this year (see the essay on Sea Ice). Similar to winter 2009-2010, winter 2010-2011 and summer 2011 had increased linkages of wind patterns between the Arctic and the sub-Arctic. This pattern is responsible for sending cold air from the Arctic southward into eastern North America and northern Europe, and warm air from the sub-Arctic northward into western Greenland and east Asia. Possibly linked to recent changes in wind patterns, ozone concentrations in the Arctic stratosphere during March 2011 were the lowest ever recorded during the period beginning in 1979. While the global increase of human sources of greenhouse gases continues, there is no direct evidence that Arctic emissions of methane are changing.

Photograph of the "Big House" at Summit, Greenland, where the SUV-150B UV spectroradiometer of the NSF Arctic Observing Network is located. Courtesy of Germar Bernhard..