Global Warming

Why Winter Is Going To Be Brutal This Year

Arctic sea ice extent for August 26, 2012 (right) was 4.10 million square kilometers (1.58 million square miles), which was 70,000 square kilometers (27,000 square miles) below the September 18, 2007 daily extent of 4.17 million square kilometers (1.61 million square miles, left). The orange line shows the 1979 to 2000 median extent for that day. The black cross indicates the geographic North Pole.

Business Insider,

14 September, 2012

We don't generally think of global warming's immediate effects, but recent studies suggest that this summer's record Arctic sea ice lows could make for a harsh winter.

Nature explains the study:

Recent research, although preliminary, suggests a connection between late-summer Arctic sea-ice extent and the location of areas of high and low atmospheric pressure over the northern Atlantic. The highs and lows can remain relatively fixed for weeks, shaping storm tracks and seasonal weather patterns such as extended cold surges.

This was seen in meteorological data from the years 1989-2011: Researchers linked the amount of sea ice in the late summer to longer cold snaps in the winter. Ralf Jaise, who led the team, suggests that the ice-less ocean sheds heat, which changes the pressure gradients in the atmosphere and weakens winds in the Northern Hemisphere, which normally sweep warm, moist air around.

"The impacts will become more apparent in autumn, once the freeze-up is under way and we see how circulation patterns have influenced the geographical distribution of sea ice," Judith Curry, a climate researcher at the Georgia Institute of Technology in Atlanta, told Nature's Quirin Schiermeier. But, she adds, "We can probably expect somewhere in the mid/high latitudes of the Northern Hemisphere to have a snowy and cold winter."