Global warming is, obviously, a world-wide phenomenon. When the concept of a 2 degrees Celsius temperature rise is discussed, it refers to the average global temperature and the effects that would have on such things as sea level rise and weather patterns. But the effects of the changing climate are not homogeneous. Very different things can happen and are happening in different places.
One such place is the coastal northeastern United States, which is a global warming hotspot. The region is heating faster than most regions of North America and, indeed, 2 degrees of summer warming has already happened in the Northeast.
New research led by the University of Massachusetts Amherst has determined that this heating is linked to significant alterations in the ocean and atmospheric conditions over the North Atlantic.
Several studies have found that the Atlantic Meridional Circulation is slowing down. The AMOC conveys warm, salty water from the tropics north towards Greenland, where it cools and sinks. The cooled water than flows back south as deep-water currents. As the warming climate melts glaciers in Greenland, the circulation slows down, less cooled water arrives in the south, and there is more heating of the ocean off the Northeastern coast.
At the same time, the North Atlantic Oscillation, a weather phenomenon that governs the strength and position of the winds that blow from the U.S. over the Atlantic, has tended to settle into a pattern that enhances the influence of ocean air on the eastern seaboard climate. Warmer ocean air being blown over the region has led to rising temperatures in Boston, New York, and Providence, Rhode Island.
As the average temperature of the world rises, some places will warm more quickly and others more slowly.
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The Coastal Northeastern U.S. Is A Global Warming Hotspot
Photo, posted August 8, 2010, courtesy of Doug Kerr via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio.
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