Yes, climate change has a hand in the California drought
Ars Technica 2015-08-25
The California drought may have put water in short supply, but debate about it is in surplus. Water use has come under even greater scrutiny as Californians struggle to deal with the current and future reality. Groundwater overuse during the drought has reached epic proportions, with the land surface in some locations sinking almost two inches per month as a result. In addition to arguing over how to use the little water they have, people are also debating the question of whether humans are partly to blame not just for water supply issues, but for the drought itself.
Late last year, a NOAA report concluded that climate change wasn’t required to explain the lack of rainfall, while a separate tree ring study found that the drought looked to be the most severe in 1,200 years. The rains have been fended off by a persistent pattern of high air pressure above the northeastern Pacific that seems to have been a product of ocean surface temperature patterns farther west.
But rainfall isn’t the only factor that contributes to drought. The heat of the day sucks moisture out of the soil, helped along by blowing winds. Boost either of those factors, and you’ll need more rainfall to keep the drought account from going in the red. Since the globe is warmer now than it was a century ago and California is part of that globe, it’s fair to guess that climate change isn’t helping.