Anthropogenic warming has increased drought risk in California

California is currently in the midst of a record-setting drought. The drought began in 2012 and now includes the lowest calendar-year and 12-mo precipitation, the highest annual temperature, and the most extreme drought indicators on record. The extremely warm and dry conditions have led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Analyzing historical climate observations from California, we find that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were warm. We find that although there has not been a substantial change in the probability of either negative or moderately…

• NS
  National Science Foundation

  Award: 0955283
• UD
  U.S. Department of Energy
• NI
  National Institutes of Health

  Awards: 1R01AI090159, 1R01AI090159-01
• NO
  National Oceanic and Atmospheric Administration