Figure 1. County-level map of federally-declared weather-related disasters between 2006 – 2011. Tornadoes and severe thunderstorms in the Midwest, and heavy rains and snows from Nor’easters, hurricanes, and other storms in the Northeast gave those two regions the most disaster declarations. An interactive version of this map that allows one to click and see the individual disasters by county is on the Environment America website.

Since 2006 , federally declared weather-related disasters in the United States have affected counties housing 242 million people–or roughly four out of five Americans. That’s the remarkable finding of Environment America, who last week released a detailed report on extreme weather events in the U.S.

The report analyzed FEMA data to study the number of federally declared weather-related disasters. More than 15 million Americans live in counties that have averaged one or more weather-related disasters per year since the beginning of 2006. Ten U.S. counties–six in Oklahoma, two in Nebraska, and one each in Missouri and South Dakota–have each experienced ten or more declared weather-related disasters since 2006. South Carolina was the only state without a weather-related disaster since 2006.

The report did a nice job explaining the linkages between extreme weather events and climate change, and concluded, “The increasing evidence linking global warming to certain types of extreme weather events–underscored by the degree to which those events are already both a common and an extremely disruptive fact of life in the United States–suggests that the nation should take the steps needed now to prevent the worst impacts of global warming and to prepare for the changes that are inevitably coming down the road.”