The big news in climate this week was the publication of a study by Susan Solomon, who testified before Congress on climate change about this time last year, on irreversible climate change. Even if we ceased emitting carbon dioxide today, Solomon and her coauthors show that we will be dealing with a thousand years of warming. And, they warn, the decline in heating due to a diminishing amount of CO2 in the atmosphere will be balanced out by the uptake of heat through the ocean, a slow process of mixing. (That's if we stopped emitting, which of course we won't.)
Solomon stressed in numerous interviews that this doesn't mean we should give up. She told NPR:
"I guess if it's irreversible, to me it seems
all the more reason you might want to do something about it," she says.
"Because committing to something that you can't back out of seems to me
like a step that you'd want to take even more carefully than something
you thought you could reverse."
But this post focuses on another finding: the drought in the Southwest associated with this warming, which they correlate on a degree basis. They write:
…changes [in precipitation in] the southwestern North America…would be [about 10%] less for 2 degrees C of global mean warming. For comparison the American "dust bowl" was associated with averaged rainfall decreases of a similar decline over 10-20 years, similar to major droughts in Europe and Western Australian in the l940's and l950's.
Note that — probably by coincidence — the pattern the models show below fits our rainfall of the last couple of years quite well. Decent precip in November, falling off over the rest of the water year.
Plus, a bonus graph…Solomon and her team correlate drought and CO2 concentrations:
Hmmmm…are we ready for the New Dust Bowl?