ALBUQUERQUE, N.M. — A conversation with a friend over the weekend regarding New Mexico’s current drought suggested some people are under the impression that current conditions are historically unprecedented. That is not the case. While the current drought is, indeed, the worst we’ve seen in more than 50 years, the drought of the 1950s was far worse.
Here’s a graph of Palmer Drought Severity Index, a commonly used measure that takes into account both how dry it is and how warm it is. A minus 3 counts as “severe drought” in the Palmer Index. Minus 4 counts as “extreme”.
Apologies for the shortcomings of the graph below, but if you look closely you can see 2012, current conditions for the previous year, count as “extreme”. And we’ve had two consecutive years below minus 3. That’s bad. But in the 1950s, we had seven consecutive years below minus 3, with three of them in the “extreme” range. We’re not there. Yet:
Source: National Climatic Data Center