Wind speed and direction are driven by differences in atmospheric pressure - air moves from areas of high to low pressure, and the greater the pressure difference between two areas, the faster the air moves. Scientists at NOAA and in academia have uncovered that recently the Arctic has been experiencing a shift in the general patterns of high and low pressures, and thus the direction and speed of the winds, and that these changes may explain some of the dramatic sea ice loss experienced in the Arctic.
Shown here is an image that compares the atmospheric pressure (geopotential height at 700 mb) experienced during June of 2007-2012 compared to the longer term average for June from 1980-2010. Much higher pressure is found directly over the Arctic Ocean and Greenland. This difference in pressure has resulted in a change in the wind patterns, shown in this second image. Orange arrows indicate the relative direction and strength (indicated by the arrow length) or winds during the 2007-2012 periods, whereas the white arrows are the 1980-2010 average. The most pronounced changes in winds can be seen over the Chuchki Sea, just northeast of Alaska and also east of Greenland.
To read more about this finding and the potential effect on Arctic sea ice, please refer to the NOAA ClimateWatch article featuring these images or the NOAA News Story.