Study highlights regional climate change hotpsots
By Bob Berwyn
Not all global warming is equal, according to scientists who just published new research on how some areas will warm much faster than others. The study, published in PLOS ONE, shows that the northeastern U.S. is already heating up much faster than the global average and will hit the 2 degree Celsius mark about 20 years before the global average climbs to that level.
“Our study shows that the northeast United States is one of those regions where warming will proceed very rapidly, so that if and when the global target is reached, we will already be experiencing much higher temperatures, with all of the related ecological, hydrological and agricultural consequences,” said Raymond Bradley, a geoscientist at the Northeast Climate Science Center (NECSC) at the University of Massachusetts Amherst. “With the signing of the Paris Agreement to try and limit greenhouse gas emissions, many people have been lulled into a false sense of security, thinking that the 2-degrees C target is somehow a ‘safe’ limit for climate change.”
The lower 48 states are projected to cross the 2-degree Celsius warming threshold about 10 to 20 years earlier than the global mean annual temperature. The researchers said “the fastest warming region in the contiguous U.S. is the Northeast, which is projected to warm by 3 degrees Clesius when global warming reaches 2 degrees Celsius.” The southwest U.S. also is projected to warm at a “much faster rate” than the southeast or southern Great Plains.
They also conclude that regional precipitation projections for warming of 1.5 degrees C and 2 degrees C remain uncertain, “but the eastern U.S. is projected to experience wetter winters and the Great Plains and Northwest are projected to experience drier summers in the future.”
“Policymakers need information that is useful at the local, not global scale. Our study provides this information for several regions in the U.S. in the context of the global temperature targets set in Paris,” said NECSC postdoctoral researcher Ambarish Karmalkar.
The authors “there is no real scientific basis to why global warming of 2 degrees Celsius should be considered ‘safe,’ (but) it emerged as ‘the least unattractive course of action’ and has been used as an easily understood, politically useful marker to communicate the urgency of the climate change problem and to drive action on a global scale.”
Use of the lower 1.5 degree number was proposed by small island nations to call attention to the worst potential impacts of rising sea levels.