Drought Marches On In The US: On The Role Of Climate Change
This summer's severe heat is widely coupled with an unpleasantly dry landscape, added fire risk, and falling crop yields, with many farmers being forced to auction off their livestock. It is possible that, by this time next year, entire communities may be forced to leave drought stricken areas, as happened during the Dust Bowl era, before the idea that human cultural practices could influence climate had ever occurred to scientists. When we wrote about national drought trends this past Spring we were concerned about fire loss in a few states and the fascinating possibility that Climate Change could favor installation of distributed, renewable electricity generation technologies. In hindsight, that seems trivializing.Five months later (see drought map for July 2006 pictured above), the severely impacted areas have broadened, shifted a bit, and encompass, also, major parts of the Northern Plains, Great Lakes, and Southeastern States. These are large scale stresses, under which, organic and factory farms alike will seriously suffer.
We speculate on three lessons from this evidence of expanding US drought.
First: just one can not properly conclude that any single weather extreme is a function of man-induced climate change, it is not possible to prove that this current drought differs significantly in causation from the one experienced 75 years ago.
Second: just as it is hypothesized that hurricane intensity is increased by global warming, it will be hypothesized, should this drought become worse, that drought intensity may be a function of global warming. That is a darn poor way to validate a climate modeling run (leading us to the final lesson).
Third: it is better to investigate and model the impacts of climate change as a basis for adaptive intervention than to wait for the economic and human pain of real drought to drive a response. Why this is not at least as interesting as hurricane risk and heat mortality is a mystery.