Scientists said that severe droughts like those in Europe, North America and China this summer have been more than 20 times as likely to occur than they would have been a century ago. It is the latest evidence that climate change is affecting food, water and electricity supplies around the world.
The researchers reported that the main driver of the droughts this year was the searing heat throughout much of the Northern Hemisphere. The scientists said that such high average temperatures would have been virtually impossible without the influence of greenhouse gas emissions.
The scientists found that soil conditions as parched this summer now have a roughly 1 in 20 chance of occurring each year in the Northern Hemisphere north of the tropics. They said global warming increased the likelihood but cautioned that the exact size of the increase had a wide possible range because of the challenges involved in estimating soil moisture at a global scale.
In many of these countries and regions, we are seeing the fingerprints of climate change, according to the science, said Maarten van Aalst, director of the Red Cross Red Crescent Climate Center and one of 21 researchers who prepared the new study as part of the World Weather Attribution initiative, a research collaboration that specializes in rapid analysis of extreme weather events.