"A massive California rain event -- one expected to occur once every 200 years -- would far surpass destruction caused by a "Big One" earthquake, causing more than $700 billion in damage and hobbling the state's economy for decades, federal scientists are warning.
U.S. Geological Survey scientists ran an extreme hypothetical, called "ARkStorm," through simulation models and determined that a deluge not seen in California since 1862 could potentially cause three times more damage than a large earthquake on the San Andreas Fault.
The 1861-62 winter storm -- what scientists call an "atmospheric river storm" -- lasted for 45 days, producing precipitation that exceeded what some areas would experience once every 500 to 1,000 years. The flooding was so bad it reduced taxable land by a third, bankrupted the state government and left parts of the Central Valley looking more like an inland sea than the fertile farming area that today forms the backbone of the state's economy."
Colin Sullivan reports for Greenwire January 20, 2011.