Berg, Neil and Hall, Alex

Geophysical Research Letters

Published date March 15, 2017

Anthropogenic warming impacts on California snowpack during drought

  • Simulates Sierra Nevada climate and snowpack during the period of extreme drought from 2011 to 2015
  • Compares first simulation to another that is identical except for the removal of the twentieth century anthropogenic warming 
  • Results show that anthropogenic warming reduced average snowpack levels by 25%, with middle-to-low elevations experiencing reductions between 26 and 43%
  • In terms of event frequency, return periods associated with anomalies in 4 year 1 April snow water equivalent are estimated to have doubled, and possibly quadrupled, due to past warming
  • Concludes that past human emissions of greenhouse gases are already negatively impacting statewide water resources during drought