Summary: To boost our fear, activists and journalists report the weather with amnesia about the past. Ten year records become astonishing events; weather catastrophes of 50 or 100 years ago are forgotten. It makes for good clickbait but cripples our ability to prepare for the inevitable. California’s history of floods and droughts gives a fine example — if we listen to the US Geological Survey’s reminder of past megafloods, and their warning of the coming ARkStorm.
” A 43-day storm that began in December 1861 put central and southern California underwater for up to six months, and it could happen again.”
— “California Megaflood: Lessons from a Forgotten Catastrophe” by B. Lynn Ingram (prof of Earth Science, Berkeley) in Scientific America, January 2013.
One of the key events in California history has disappeared from our minds. For a reminder see this by the US Geological Survey.
“Beginning on Christmas Eve, 1861, and continuing into early 1862, an extreme series of storms lasting 45 days struck California. The storms caused severe flooding, turning the Sacramento Valley into an inland sea, forcing the State Capital to be moved from Sacramento to San Francisco for a time, and requiring Governor Leland Stanford to take a rowboat to his inauguration. William Brewer, author of Up and Down California in 1860-1864, wrote on January 19, 1862, ‘The great central valley of the state is under water — the Sacramento and San Joaquin valleys — a region 250 to 300 miles long and an average of at least twenty miles wide, or probably three to three and a half millions of acres!’
‘In southern California lakes were formed in the Mojave Desert and the Los Angeles Basin. The Santa Ana River tripled its highest-ever estimated discharge, cutting arroyos into the southern California landscape and obliterating the ironically named Agua Mansa (Smooth Water), then the largest community between New Mexico and Los Angeles. The storms wiped out nearly a third of the taxable land in California, leaving the State bankrupt.
“The 1861-62 series of storms were probably the largest and longest California storms on record. However, geological evidence suggests that earlier, prehistoric floods were likely even bigger. There is no scientific evidence to suggest that such extreme storms could not happen again. However, despite the historical and prehistorical evidence for extreme winter storms on the West Coast, the potential for these extreme events has not attracted public concern, as have hurricanes. The storms of 1861-62 happened long before living memory, and the hazards associated with such extreme winter storms have not tested modern infrastructure nor the preparedness of the emergency management community.”
For an account of the flood from that time see this by J. M. Guinn; an excerpt from Exceptional Years: A History of California Floods and Drought (1890).