Abstract

Records of April 1 snow water equivalent (SWE) are examined here using multiple linear regression against reference time series of temperature and precipitation. This method permits an examination (1) of the separate roles of temperature and precipitation in determining the trends in SWE; (2) the sensitivity of SWE to warming trends, and its distribution across western North America and as a function of elevation; and (3) inferences about responses of SWE to future warming. These results emphasize the sensitivity to warming of the mountains of northern California and the Cascades of Oregon and Washington. In addition, the contribution of modes of Pacific climate variability is examined and found to be responsible for about 10-60% of the trends in SWE, depending on period of record and climate index.