© Getty Images
Full water levels are visible behind the Folsom Dam at Folsom Lake on July 20, 2011, in Folsom, Calif. Low water levels are shown on Aug. 19 in Folsom, Calif.
California is in the third year of one of the state's worst droughts in the past century, one that's led to fierce wildfires, water shortages and restrictions, and potentially staggering agricultural losses.
The dryness in California is only part of a longer-term, 15-year drought across most of the Western USA, one that bioclimatologist Park Williams said is notable because "more area in the West has persistently been in drought during the past 15 years than in any other 15-year period since the 1150s and 1160s" - that's more than 850 years ago.
"When considering the West as a whole, we are currently in the midst of a historically relevant megadrought," said Williams, a professor at the Lamont-Doherty Earth Observatory of Columbia University in New York.
Megadroughts are what Cornell University scientist Toby Ault calls the "great white sharks of climate: powerful, dangerous and hard to detect before it's too late. They have happened in the past, and they are still out there, lurking in what is possible for the future, even without climate change." Ault goes so far as to call megadroughts "a threat to civilization."
What Is A Megadrought?
Megadroughts are defined more by their duration than their severity. They are extreme dry spells that can last for a decade or longer, according to research meteorologist Martin Hoerling of the National Oceanic and Atmospheric Administration.
Megadroughts have parched the West, including present-day California, long before Europeans settled the region in the 1800s.
Comment: Climate change is more likely due to Fireballs and Comets.
See also:
Climate Change Swindlers and the Political Agenda
Sott.net Series on Comets & Catastrophes