Based on hydrological model simulations and a new snowmelt tracking algorithm, we show that 53% of the total runoff in the western United States originates as snowmelt, despite only 37% of the precipitation falling as snow. In mountainous areas, snowmelt is responsible for 70% of the total runoff. By 2100, the contribution of snowmelt to runoff will decrease by one-third for the western U.S. in the IPCC RCP8.5 scenario. Snowmelt-derived runoff currently makes up two-thirds of the inflow to the region’s major reservoirs. We argue that substantial impacts on water supply are likely in a warmer climate.
2017), How much runoff originates as snow in the western United States, and how will that change in the future?, Geophys. Res. Lett., 44, doi:10.1002/2017GL073551., , , , and (
“Climate change is shrinking the West’s water supply : Three new studies show dry times ahead.” http://www.hcn.org/issues/49.10/climate-change-is-shrinking-the-wests-water-supply All three studies point to the influence of a warming climate. “Climate change is real, it’s here now, it’s serious and it’s impacting our water supplies in a way that will affect all of us,” says Bradley Udall, a water and climate researcher at Colorado State University.
? “The twenty-first century Colorado River hot drought and implications for the future,” Water Resources Research, February/March 2017. http://onlinelibrary.wiley.com/doi/10.1002/2016WR019638/full
? “Large near-term projected snowpack loss over the western United States,” Nature Communications, April 2017. https://www.nature.com/articles/ncomms14996
? “Depletion and response of deep groundwater to climate-induced pumping variability,” Nature Geoscience, January 2017. http://www.nature.com/ngeo/journal/v10/n2/full/ngeo2883.html