When can we expect extremely high surface temperatures?
Sure glacier melt, sea level rise, extreme drought, and species loss get all the media attention — they are the Britney Spears, Paris Hilton, and Barack Obama of climate impacts. But what about good old-fashioned sweltering heat? How bad will that be? Two little-noticed studies — one new, one old — spell out the grim news.
Bottom line: By century’s end, extreme temperatures of up to 122°F would threaten most of the central, southern, and western U.S. Even worse, Houston and Washington, DC could experience temperatures exceeding 98°F for some 60 days a year.
The peak temperature analysis comes from a Geophysical Research Letters paper published two weeks ago that focused on the annual-maximum “once-in-a-century” temperature. Researchers looked at the case of a (mere) 700 ppm atmospheric concentrations of CO2, the A1b scenario, with total warming of about 3.5°C by century’s end. The key scientific point is that “the extremes rise faster than the means in a warming climate.”
More… (click through to see a great temperature map) 
