Scientists agree that the current drought is caused by extreme atmospheric pressure that prevented winter storms from reaching the state during last year and this year’s rainy seasons.
Daniel Swain, lead author of the study, called the system that blocked wind patterns “the ridiculously resilient ridge” in the northeastern Pacific Ocean.
He says the study found that human-caused greenhouse gases played a role.
“The risk of seeing an event like the 2013 resilient ridge event has increased due to climate change but that’s a slightly indirect indicator of drought,”says Swain.
The pressure region was unusual because of its size and its longevity. The research is one of the most comprehensive studies to investigate the link between climate change and California’s drought.