Presenter(s): Carson Schmittle − English
Faculty Mentor(s): Dave Sutherland
Poster 182
Research Area: Natural Science
Mountain snowpack acts as an important natural reservoir for much of California. In the Sierra Nevada mountain range, it builds primarily through snow, accumulated in winter storms. We measure the amount of water stored in a snowpack as the snow water equivalent (SWE), which is dependent on both the density of the snow and the thickness of snow. In recent years, the mean peak measurement of SWE in the Sierra Nevada has declined dramatically. Here, I demonstrate that decreased precipitation, in conjunction with greater surface temperatures, is the primary factor in the downtrend of snowpack in this mountain range. The accumulation of soot and dust also contributes to snowpack depletion (by reducing average albedo and increasing melt rates), but I predict that lesser precipitation correlates most strongly to the observed retreat of snowpack. This is evidenced by comparing available climate data with trends in peak annual SWE. Precipitation in a cold climate collects as snow, while precipitation in a warmer climate falls as rain and actually does more to melt snow. Therefore, the heavier and more infrequent precipitation predicted for the coming century will translate to less snow accumulated in the winter and more snow melted in the spring and summer. Snowpack provides a tremendous amount of water to California for agricultural, industrial, and recreational purposes, so future infrastructure development must prepare for snowpack depletion.