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.”
The results, depicted above (in °C),