Study: Winter tornadoes to get more powerful as world warms

By SETH BORENSTEIN
AP Science Writer

A new study says winter tornadoes, like the devastating one that hit five states last week, are likely to be stronger and stay on the ground longer as the world warms. Monday’s study released at a science conference takes two early nasty tornadoes _ one in winter and one in spring _ and simulates the conditions in the end of the 21st century if carbon dioxide emissions keep rising in a worst-case scenario. Researchers see the biggest change for winter tornado. They find that a 2013 winter tornado that injured 82 people would have nine times the power in a warming world.