It's been unbearably hot and dry this week, as is not unusually the case in this part of Southern California in early September…but could the extreme dryness of the state be contributing to our heat wave?
An attribution study — looking at the possible contribution from climate change to extreme weather events –from the American Meteorological Society, with a chapter on the extreme heat wave that hit the Midwest last year by Noah Diffenbaugh, a climatologist at Stanford, makes clear that yes, the dryness makes heat all the more likely. To wit:
…record rainfall deficits played a critical role in shaping the 2012 severe heat [in July the Midwest]. Given the considerably lower signal-to-noise ratio of the summer precipitation response to global warming over the central and eastern United States (relative to the summer temperature response; e.g., (Diffenbaugh et al. 2011), occurrence of the most severe heat events is likely to continue to be strongly regulated by rainfall variability.
In other words, dry winters lead to parched plants, which transpire much less water vapor, making rain less likely. (True, this is more of a factor in the Midwest than in California, but forecasters repeatedly warned of flash floods in our mountains this week and last…but nada, unfortunately.)
The heat and lack of rain is not a problem for Congressional Republicans, however, who have a simple method for dealing with these questions, as seen in the work of Pulitzer Prize-winner Mike Luckovich: