Calif. drought leads to lowest snowpack in 500 years

California’s years-old drought has led to the lowest overall snowpack in the state since at least the 1500s, according to a new study released on Monday.  The study, published in the journal Nature Climate Change, concluded that the snowpack in California’s Sierra Nevada mountains was only 5 percent of its historic average this past spring. The researchers used monitoring stations and combed tree ring records to get a handle on historic winter snowfall totals and determined that “the 2015 low is unprecedented in the context of the past 500 years.” Because melting snow is responsible for 30 percent of California's overall annual water supply, the snowpack level is especially important for alleviating drought conditions in the state. Researchers said the levels “present an ominous sign of the severity of this drought.”...more