Global warming makes drought worse

"California Drought Is Made Worse by Global Warming, Scientists Say"

A recent NY Times piece (Justin Gillis, 8/20/15) picked up on a new study showing how the California drought is being intensified by rising temperatures. The study, led by Park Williams of Columbia, calculated that the drought was about 15-20% more intense than it would have been under slightly cooler (natural) conditions. Why is this? We'll discuss it in class and post the answer later!

The original paper is here (free access from UA campus, otherwise behind paywall).

Photo from the NYT story.