A batch of twisters ripped through Illinois this week, flattening homes and causing injuries and at least two confirmed deaths. The storm-caused havoc is a reminder that spring is tornado season in the United States. These photos show hurricanes, rainstorms, and other types of extreme weather around the world. Scientists predict that these storms will change as global temperatures rise, but not in the way you might think.
Many scientists don’t expect the total number of storms to increase (some think it might decrease); rather, they expect hurricanes and rainstorms to become more severe.
According to Michael Wehner, senior staff scientist in the Computational Research Division at the Lawrence Berkeley National Laboratory, these changes will likely become noticeable with a rise of 2°C in the average global surface temperature.
“Definitely, at two degrees, there will be large changes to the number of Category 4 and Category 5 storms, and the very strongest storms will be stronger,” he says. “You often read that two degrees is some arbitrarily safe form of climate change. I take issue with that. This whole thing about two degrees being safe, I think, is nonsense.”
Although hurricane wind speeds will probably increase, tornados are a different story. Some scientists predict that climate change won’t affect the total number or the severity of tornadoes, but that tornadoes will occur closer together.
“Back in the 1970s, we had about 150 days per year that had an F1 [tornado] or stronger. In the last decade, we had about 100,” says Harold Brooks, senior research scientist at NOAA’s National Severe Storms Laboratory. “We’re having fewer days [of tornadoes],” Brooks says; what is increasing is multiple tornadoes occurring in a single day.
What does this mean for us? According to Kerry Emanuel, professor of atmospheric science at Massachusetts Institute of Technology, we won’t be able to adapt fast enough to these changes. To illustrate, he referenced Haiyan, a 2013 typhoon in the Philippines.
“The Philippines get hammered by typhoons all the time, and yet you don’t read about it on the news because that society is pretty strongly adapted to hurricanes,” he says. “[Haiyan] was just a little bit beyond what they were used to. A lot of the people died in shelters that had ridden out other typhoons.”
“You don’t need to change the intensity [of storms] very much to bring it very much outside what people are used to,” he says. “It’s happening so fast that that’s really the problem—we can’t adjust to it.”
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