Researchers use warm and cold fronts to predict the movement of tornadoes, but now they may be looking to the seas.
New research suggests looking at the Pacific Ocean's temperature could be an effective way to determine the "type and location" of tornado activity in the U.S., a University of Missouri-Columbia news release reported.
Laurel McCoy, an atmospheric science graduate student at the MU School of Natural Resources, and Tony Lupo, professor and chair of atmospheric science in the College of Agriculture, Food and Natural Resources went through data from 56,45 "tornado-like events" dating as far back as 1950.
The team found that when Pacific surface temperatures were warmer there was a 20.3 percent higher chance of the formation of a tornado that was EF-2 to EF-5on the Enhanced Fuijta (EF) scale. The cale rates the intensity of tornados from zero to five by the amount of damage they inflict.
The team also found that warmer surface temperatures increased the chance of tornado formations either west or north of Tornado alley, an area in America's Midwest known for an exceptional amount of tornado-like weather.
McCoy noticed when surface temperatures were cooler Tennessee, Illinois and Indiana experienced more tornados that rolled in from southern states.
"Differences in sea temperatures influence the route of the jet stream as it passes over the Pacific and, eventually, to the United States," McCoy said. "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."
McCoy and Lupo analyzed the relationship between tornadoes and something called the Pacific Decadal Oscillation (PDO). A PDO is a "long-term temperature trends that can last up to 30 years." NASA believes we have recently entered a cool phase.
"PDO cool phases are characterized by a cool wedge of lower than normal sea-surface ocean temperatures in the eastern Pacific and a warm horseshoe pattern of higher than normal sea-surface temperatures extending into the north, west and southern Pacific," McCoy said. "In the warm phase, which lasted from 1977 to 1999, the west Pacific Ocean became cool and the wedge in the east was warm."
In 2011 there were 550 tornado-related deaths; this new method of prediction could help save lives in the future.
"Now that we know the effects of PDO cool and warm phases, weather forecasters have another tool to predict dangerous storms and inform the public of impending weather conditions," McCoy said.
