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?
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Looking back, the long-term record also shows some staggeringly wet periods. The decades between the two medieval megadroughts, for example, delivered years of above-normal rainfall — the kind that would cause devastating floods today.
The longest droughts of the 20th century, what Californians think of as severe, occurred from 1987 to 1992 and from 1928 to 1934. Both, Stine said, are minor compared to the ancient droughts of 850 to 1090 and 1140 to 1320.
