According to the National Climate Assessment, climate change has already affected the US in significant ways. This map from the NY Times shows the change in temperatures from around the country, specifically the “1991-2012 average temperature compared with 1901-1960 average”.
One of the report’s most striking findings concerned the rising frequency of torrential rains. Scientists have expected this effect for decades because more water is evaporating from a warming ocean surface, and the warmer atmosphere is able to hold the excess vapor, which then falls as rain or snow. But even the leading experts have been surprised by the scope of the change.
The report found that the eastern half of the country is receiving more precipitation in general. And over the past half-century, the proportion of precipitation that is falling in very heavy rain events has jumped by 71 percent in the Northeast, by 37 percent in the Midwest and by 27 percent in the South, the report found.
Nonlinear systems, man.