The far western United States set records for low snowpack levels in 2015, and a new report blames high temperatures rather than low precipitation levels.
The new study suggests greenhouse gases were a major contributor to the high temperatures. The study was published Monday in the journal Geophysical Research Letters.
Scientists looked at snow measurement sites in California, Oregon, Washington, western Nevada and western Idaho. They found that in 2015, more than 80 percent of those sites experienced record low snowpack levels as a result of much warmer-than-average temperatures.
Most of the previous records were set in 1977.
The snow drought led the governors of California, Oregon and Washington to order reductions in water use.