Keeping tabs on the temperature of the Pacific Ocean could help scientists predict tornado activity in the continental United States, according to a new study.
Surveying more than 56,000 tornado-like events from 1950 to 2011, researchers from the University of Missouri found that higher-than-average ocean temperatures corresponded with a 20 percent increase in tornados, usually in the west and north of the so-called “Tornado Alley” of the midwest. When sea surface temperatures were lower, more tornados tracked from southern states into Tennessee, Illinois and Indiana.
“Differences in sea temperatures influence the route of the jet stream as it passes over the Pacific and, eventually, to the United States,” said Laurel McCoy, an atmospheric graduate student at the university’s School of Natural Resources. “Tornado-producing storms usually are triggered by, and will follow, the jet stream. This helps explain why we found a rise in the number of tornados and a change in their location when sea temperatures fluctuated.”
By studying the relationship between tornadoes and long-term temperature trends called Pacific Decadal Oscillation, McCoy said weather forecasters will be better equipped to predict dangerous storms.
The research was presented at the National Weather Association Conference this week in South Carolina.