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Bridging climate science, citizens, and policy

US Drought Conditions Intensify Over Central US; Hold Mainly Steady Elsewhere


The US drought got progressively worse in the past week over most of the middle of the US.  For the remainder of the country, some places witnessed worsening drought conditions while other areas saw some small amount of relief.

According to the US Drought Monitor’s weekly update, “The August 7 Drought Monitor map shows 52.27 percent of the United States and Puerto Rico in moderate drought or worse, compared to 52.65 percent last week; 38.48 percent in severe drought or worse, compared to 38.12 percent a week earlier; 20.18 percent in extreme drought or worse, up from 18.62 the previous week; and 3.51 percent in exceptional drought, up from 2.52 percent last week.”

So extreme and exceptional drought areas expanded slightly compared to the previous week.  But the overall area affected by moderate drought or worse was essentially unchanged.


Figure 1 – Drought conditions across the US as of 7 August 2012.  Exceptional drought areas in Missouri, Arkansas, Oklahoma, Kansas, Nebraska, and Illinois grew in the past week.  Some relief of drought conditions occurred in South Dakota, Wyoming, and Arizona.

This drought is not expected to be significantly relieved before October.  Hopefully, weather conditions in the next two months prove that prediction wrong or the effects of this drought will be further reaching and longer lasting than what people currently think.  This is a good time to examine current drought-related policies and determine whether or nor they are equipped to deal with early 21st century drought conditions.  If they aren’t, it seems reasonable to conclude they won’t be able to handle late 21st century drought conditions either.  For example, Georgia farmers have begun irrigating crops.  That practice reduces above ground streamflow, depriving aquifers the chance to recharge.  Millions of people in the southeast depend on aquifer water for drinking.  Which interest will win if the drought continues another 10 years?  Do people get drinking water or do farmers get irrigation water?  And that’s just one potential impact.  The time to think and plan for this is now, before the problems grow in magnitude and complexity.


3 thoughts on “US Drought Conditions Intensify Over Central US; Hold Mainly Steady Elsewhere

  1. Have you seen the reports about 40,000 Sturgeon killed by river water exceeding 97F in Nebraska? Has this happened elsewhere; and if not why not? Presumably 97F is a critical temperature for Sturgeon in particular; and they only inhabit(ed) the river in question… How the heck does flowing river water ever get to 97F? It must have been very shallow and hardly moving… If so, why didn’t the Sturgeon go elsewhere? Is this another instance of “frog in a saucepan of water being boiled” (i.e. the frog never jumps out because dT/dt is too low)?

    • I did see the reports. Without providing source material, yes I have seen this occur elsewhere. As I’m sure you’re aware, every species has a range of environmental conditions in which they are well adapted and can most easily survive. Outside of this range, stresses can amplify each other and large die-offs occur; sturgeon and mountain pine trees being only 2 examples.

      Water and soils stay warm when night temperatures do not decrease as much as normal. I heard about low temperatures across the Midwest US in the low-80s for a couple of weeks during the summer. Combine that with highs of 100-110 and water has no choice but to warm up in response. I don’t think the problem was terribly extensive. The conditions were probably unique to select areas. Could the sturgeon have gone anywhere? I’m not sure. They’re obviously more mobile than trees, for instance.

      We can expect to see more reports like this due to two factors. The first is probably more important in the short-term: we’re observing the planet in ways that have never been observed before, so there are bound to be conditions like this that shock us since they’re anomalous. Did they happen before widespread observation networks were put in place? The second factor is obvious: as the globe warms, more and more species will be impacted. How they respond will be key to their ultimate long-term survival.

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