Effect of global warming on Sierra Nevada mountain snow storage

Snowmelt runoff processes in an alpine watershed located in the Sequoia National Forest are analyzed using an energy-based snowmelt runoff model. Using a global warming scenario, the results of the analysis indicate that the hydrograph of snowmelt runoff shifts between 19 and 93 days earlier and the snow season ends between 25 and 68 days earlier at an elevation of 2800 m. The most striking change is a decrease in the snow/precipitation ratio at elevations below 2300 m. Here the ecological balance suffers a major impact due to a small increase in air temperature that causes a significant amount of snow to occur as rain. In addition, the shorter snow season decreases the albedo of the land surface since the albedo of snow is much higher than that of vegetation or soil. As a consequence, regional warming is increased due to a snow albedo feedback process.