It’s impossible to avoid wondering in this year of strange weather what impact climate change may have had on this monstrously powerful tornado. The truth is, however, there’s no clear answer. A 2012 U.N. Intergovernmental Panel on Climate Change report on global warming and extreme weather concluded that it was likely that man-made carbon emissions were already contributing to stronger and longer-lasting heat waves—much like the ones experienced through the U.S. last year, which went down as the hottest year for the continental U.S. on record. There’s also confidence that carbon emissions and other greenhouse gases are leading to more extreme rainfall events and more intense droughts, like the one that is still suffocating much of the Midwest.
As hotter air can hold more moisture, climate change seems likely to create the fuel for heaving hurricanes and other storms. Key ingredients for severe thunderstorms include warm, moist air to fuel thunderstorm initiation and growth and winds that change with altitude, or wind shear, to help organize a thunderstorm and create rotation. Big changes of wind with height, or high wind shear, are especially important for tornado and hail formation. But since one major factor favors a more conducive environment for severe thunderstorms to spark with a warming climate and another is less conducive for severe thunderstorm organization, it is very difficult to determine how severe weather will change in the future.
Kemo D. 7