We tend to forget droughts as quickly as the next rain, so we may not remember that we’ve been in the situation before and it had nothing to do with man-made global warming. California is known for weather extremes. Early settlers felt the Sacramento valley was unsuitable for farming because it was too wet, flooding had people paddling around what is now Sacramento. Much later we had a pretty bad drought in the mid1970s that lasted two years. However, this drought is breaking records. In fact, scientists are saying it may exceed any other drought since we’ve been keeping records, roughly 136 years. But, looking back much farther, we find evidence of dry periods lasting much longer.
Through studies of tree rings, sediment and other natural evidence, researchers have documented multiple droughts in California that lasted 10 or 20 years in a row during the past 1,000 years — compared to the mere three-year duration of the current dry spell. The two most severe megadroughts make the Dust Bowl of the 1930s look tame: a 240-year-long drought that started in 850 and, 50 years after the conclusion of that one, another that stretched at least 180 years.
“We continue to run California as if the longest drought we are ever going to encounter is about seven years,” said Scott Stine, a professor of geography and environmental studies at Cal State East Bay. “We’re living in a dream world.”California in 2013 received less rain than in any year since it became a state in 1850. And at least one Bay Area scientist says that based on tree ring data, the current rainfall season is on pace to be the driest since 1580 — more than 150 years before George Washington was born. The question is: How much longer will it last?