Roy W. Spencer, Ph. D.
With more rain and snow on the way, the supposed “unending drought” that the New York Times reported on last year has, in a matter of weeks, ended — at least in Northern California.
Yesterday’s color satellite imagery from NASA shows the dramatic changes which have occurred since the same date three years ago:
– Widespread and deep snowpack
– Greening vegetation
– Rivers overflowing their banks
– Strong river discharge into the Pacific Ocean
The drought may be over for now, with a feeble La Niña climate pattern in the Pacific, but there is a good possibility that it will return. In the early 1800s, the sun experiences two solar cycles with reduced sun spots, solar cycle five and six. A period knows at the Dalton Minimum. According to the California Mission records, during the period between 1798 and 1823, there was a 13-year drought, followed by three wet years, and then six more years of more drought, then a more regular pattern emerged.
With Solar Cycle 24 and 25 following similarly reduced sunspots a pattern similar to solar cycles five and six, it is possible that California could see similar drought patterns, long years of drought interrupted by shorter term wet periods. If this is true, we should expect the drought return after two-three years of moisture. Only time will tell. In the meantime continues to save the water we have stored, as it may come in handy in a few years, as we still have to live through solar cycle 25 which is predicted to have even fewer sunspots than solar cycle 24.
There is also the possibility that the larger drought driving forces are the Pacific climate patterns show in this illustration from The West without Water: What Past Floods, Droughts, and Other Climatic Clues Tell Us about Tomorrow by B. Lynn Ingram and Frances Malamud-Roam
The solar cycles average 11 years in length, where some droughts in the Southwest, including California, have lasted 25 to 50 years in length according to paleoclimatology. The solar connection to droughts is still being studied and explored. Be thankful for the rain and show we have, it may have to last us for 25 plus years.