The United States and the world experienced a barrage of extreme weather events over the last several years consistent with what climate scientists have been predicting from global warming pollution.  Indeed this summer, U.S. weather was almost apocalyptic: searing heat, ferocious fires, hurricanes, and severe storms left people injured, homeless and in some cases, dead.

Scientists have been investigating the link between extreme weather events and man-made global warming for years.  They now generally agree that global warming pollution plays a role, along with natural factors such as El Niño or La Niña, in shifting the odds toward extreme events. In fact, NOAA recently concluded, after looking through 50 years of weather data, that droughts like the record 2011 Texas drought was made “roughly 20 times more likely” because of global warming. 16  Indeed, observations have shown that certain extremes—high heat, heavy precipitation and floods, duration and intensity of droughts and extremes related to higher sea levels—have increased over the last half of the century.