Spatiotemporal SWE Variability of the Columbia River Basin

Understanding the spatial and interannual variability of snowpack in montane regions such as the western U.S. is a key component of water management. Studies in this vein have typically focused on west wide analyses and found correlations with the El Nino Southern Oscillation and the Pacific Decadal Oscillation. However, smaller scale, subregional analyses may offer different insights into the spatiotemporal variability of snowpack which may be useful for water management at local scales as well as ecological assessments and planning. We consider March 1, April 1, and May 1 snow water equivalent at 243 sites within the Columbia River Basin over the years 1983-2012. A rotated principal component analysis is performed and resulting scores and loadings are correlated with a range of topographic and climatic variables. The first and second components of April SWE are strongly linked to latitudinal shifts in the jet stream. The second component is also correlated with the occurrence of Pineapple Express events. The third component is strongly correlated with interannual temperature and precipitation variability.