Global Crisis/Innovation Blog

If We Have Global Warming, Why Do We Have Global Cooling?

By Shlomo Maital

  Count on the global warming deniers to ask:  if we have global warming, why do we have global cooling (freezing snowy winters in America and in Europe, closing airports, stranding travellers, and causing chaos)?  And count on journalists to cover the results of the blizzards, but never to ask the core question, how are global cooling and global warming related?

    Fortunately, Judah Cohen, a meteorologist who works for a weather forecasting company, has written a short essay answering this question.   Here is a short summary of Cohen’s explanation.

1.  Even as frozen areas like the polar caps shrink, seasonal snow cover has increased,  across the high latitudes of the northern Hemisphere, especially in Siberia, and the Himalayas.  As global temperatures warm, Arctic sea ice melts, creating more moisture available to fall as snow. 

2.  The sun’s energy reflects off the snow and escapes back to space, cooling the air; this creates an “unusually large dome of cold air next to the mountains”, amplifying the standing waves in the atmosphere.

3. The increased wave energy disturbs the jet stream, which, instead of flowing mainly west to east, as it does normally, meanders more north and south.  In winter, this change in snow sends warm air north, but also pushes cold air south from the arctic and from Siberia. 

4.  “This is why Eastern US, Northern Europe and East Asia have experienced extraordinarily snowy and cold winters since the year 2000.” 

Why did forecasts fail to predict them?  “Because the primary drivers in meteorological models are the oceans, which have been warming…. They have ignored the snow in Siberia!”.

  It’s all a “snow job”, concludes Cohen.  We’re freezing not in spite of climate change but because of it.  Looks like the meteorologists’ forecast models were as wrong as the financial experts’ models. 

* Judah Cohen, Global New York Times, Dec. 25, 2010

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