Last month, hailstones as big as baseballs pounded the Denver area, knocking down power lines, damaging homes, and smashing through windshields “like tissue paper,” The Washington Post reported. The hailstorm hit during rush hour, when lots of cars where on the road, and ended up being Colorado’s costliest catastrophe, totaling $1.4 billion in damages. But if climate change goes unchecked, we might see more of these extreme hailstorms in the future, according to new research.
A study published today in Nature Climate Change shows that in the second half of this century, North America could experience fewer hail days overall, but storms with larger hail might become more common, including hail that’s larger than 1.6 inches — exactly like the hailstorm that plummeted Denver. This is bad news across the board: hail can destroy crops, as well as homes and cars, leading to more insurance losses.
Predicting how hail will change due to global warming is very complicated. Hail forms during thunderstorms, when fast air currents carry water droplets up in the sky, where they freeze into hailstones. As more water freezes around them, these lumps of ice become too heavy and fall onto the ground as hail. Predicting such small-scale events is difficult. In this study, researchers used several models to simulate how hail might form and grow over North America between 2041 and 2070, if the world keeps warming up.
Southeastern states like Florida could be lucky
They found that while hail days in the summer and spring might decrease overall, storms with large hail — 0.4 to 1.6 inches — might become more common, especially in the central and northern plains of the US. Areas like eastern Colorado, Nebraska, and southern South Dakota might see an increase in hail that’s larger than 1.6 inches, the study says. Southeastern states like Florida, instead, could be lucky: they might experience fewer hailstorms and with smaller hail.
The results provide “an important and much needed insight” into how climate change will affect hail, John Allen, an assistant professor of meteorology at Central Michigan University, writes in an article published alongside the Nature Climate Change paper. However, models always leave room for uncertainty, and the ones used in the study can’t simulate individual thunderstorms that produce hail, Allen says. So these predictions are not the final word.
Still, knowing whether the future might hold more hailstorms like the one that pounded Denver last month might help us prepare better. (Should we develop hardier crops that resist hail? Should farmers invest in nets that can protect their crops?) Studying all this “is a pressing need for future research,” Allen concludes.