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.
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“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.
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