More Abnormal Winter Weather is Likely for US

Scientific American: Climate & Weather

“The Winters of Our Discontent”

By Charles H. Greene, Director of the Ocean Resources and Ecosystems Program, Cornell University.

The full article was published in Scientific American, Volume 307, December 2012, pages 50 thru 55 and online on November 13, 2012.

Loss of Arctic sea ice is stacking the deck in favor of harsh winter weather in the United State and in Europe. 

The past three winters in parts of North America and Europe were unusual.  First, during the winters of 2009 thru 2011, the eastern seaboard of the US and western and northern Europe endured a series of exceptionally cold and snowy storms – including the February 2010 “snowmageddon” storm in Washington, DC, that shut down the federal government for nearly a week.  

The winter of 2011 – 2012 brought even more surprises. The eastern US had one of its mildest winters on record, while other parts of North America and Europe were less fortunate. In Alaska, the average January temperature was a full 18 Fahrenheit degrees colder than the long term average. Europe saw extreme frigid temperatures and snowdrifts that were roof high. By mid-February, more than 550 deaths were due to these conditions.

How can we explain these outbreaks of severe weather during the past decade that was the warmest in the 160 years where instruments have tracked the global average temperatures: it appears to be caused by the record-breaking losses of summer sea ice in the Arctic Ocean.

• Global warming has increased the loss of summer sea ice in the Arctic, which has altered atmospheric conditions that influence winter weather in the U.S. and Europe.
• A weakened Jet Stream exhibits larger waves in its pathway, which can get stalled in place, locking an affected region such as the northeastern U.S. in a prolonged deep freeze.
• The changes lead to invasions of Arctic air into the middle latitudes, increasing the likelihood of severe winter outbreaks, which occurred in the eastern U.S. and northern Europe in 2010 and 2011 and in eastern Europe in January 2012.
• The deck may be stacked for harsh outbreaks during the 2012–2013 winter in North America and Europe.

Note: The Winter of Our Discontent, published in 1961, is John Steinbeck’s last novel. The title is a reference to the first two lines of William Shakespeare‘s Richard III: “Now is the winter of our discontent / Made glorious summer by this sun [or son] of York,…”