Is political spin making the drought look worse?

Today, two readers questioned the annual Santa Rosa rainfall average published by The Press Democrat.  A comment attached to our drought editorial said: “We will always be in drought because the annual average rainfall went from like 25 inches to over 30 inches overnight.  I smell politicians cooking the books somewhere.” A letter raised the same issue in less colorful language.

The question is good, and it deserves a response.  The answer is the figure we’re using is accurate and the average hasn’t changed for almost 10 years.

Annual rainfall averages are calculated by the National Climatic Data Center, a federal agency, and they’re updated once every 10 years, based on 30 years of data.  The most recent update was in 2001 and increased the annual average for Santa Rosa from 30.3 inches to 31.01 inches.  The next update will be next year.  The same agency has a 75-year average posted on its Web site.  For Santa Rosa, it shows an average of 30.5 inches of rain annually from 1931 through 2005.

Here’s a link to the climate center Web site, and here’s another to a 2001 article about the last update of Santa Rosa’s rainfall average.

— Jim Sweeney