While in the midst of the cold embrace of the New England winter, it can be easy to dismiss reports of global warming and climate change, but there is actually strong scientific evidence, says the National Ice and Snow Data Center (NISDC)
Arctic Sea Ice News & Analysis ,that the breakdown of a weather pattern known as the polar vortex due to Arctic warming is one of the primary causes of 2011's unusually cold and snowy winter.
While New England and much of the U.S. was being buried in snow and seeing extended periods of Arctic cold, the NISDC says,
the Arctic was experiencing air temperatures ranging from 4 to 11 degrees warmer than average. The proximate cause was wind patterns associated with the negative phase of the Arctic oscillation, and heat being released into the air from a wider than usual expanse of unfrozen arctic seas.
So how does that translate into colder winters in the lower 48? A weather phenomena known as the polar vortex weakens as Arctic temperature increase. In normal years, this polar vortex fueled by dense cold air around the polar region, causes a circular wind pattern that traps the coldest arctic air near the poles according to both the NISDC and a report by National Oceanic and Atmospheric Administration (NOAA) scientists.
Arctic Report Card - Atmosphere - Overland, et al.
In what NOAA calls a Warm Arctic-Cold Continents Pattern,-
Future of Arctic Sea Ice and Global Impacts - Warm Arctic - Cold Continents the weakening of the polar vortex allows cold Arctic air to break away from its usual Arctic home and head south. The influx of cold Arctic air into the mid-latitudes, including New England and much of the U.S. can continue for extended periods of time, lasting as long as the polar vortex remains weakened by increased arctic air temperatures.
Get Used to Colder Winters in New England
Furthermore,
as global warming intensifies, increasingly scarce Arctic sea ice is expected to bring about conditions more favorable to prolonged negative phase Arctic oscillation conditions. That means that those of us in New England and the rest of the mid-latitudes will need to start getting used to much colder and snowier winters than those of past decades. While global warming may bring prolonged heat waves and higher temperatures to New England's summers, it appears that it may have just the opposite effect on our already challenging winters.
Lest you think this is the brainchild of one or two U.S. government research centers, the linkage between warmer than normal Arctic winters and colder than normal mid-latitude winters has also been documented for Europe and Asia by researchers Vladimir Semenov and V. Petoukhov as published in the "Journal of Geophysical Sciences -Atmosphere" in 2010.-
A link between reduced Barents-Kara sea ice and cold winter extremes over northern continents - OceanRep Japanese researchers Honda, Inoue, and Yamane published their findings of similar low arctic sea-ice influences on Eurasian winters in "Geophysical Research Letters" in 2009. -
Influence of low Arctic sea‐ice minima on anomalously cold Eurasian winters
