Climate Change Impacts on Snow, Glaciers, and Water Resources in the Pacific Northwest
Speaker: Anne Nolin, Department of Geosciences, Oregon State University
Series: CEE Departmental Seminars
Location: Bowen Hall Auditorium
Date/Time: Monday, February 28, 2011, 4:30 p.m. - 6:00 p.m.
The snowmelt-dominated Cascade Mountains provide critical water supply for agriculture, hydropower, ecosystems, and municipalities throughout the Pacific Northwest. Empirical analyses and models of projected climate change show rising temperatures in the region and a shift from snowfall to rainfall at lower elevations. Glacier meltwater runoff is also affected by the warming climate. This presentation shows results from two studies that examine watershed scale responses of climate change. In the first study of a snowmelt-dominated watershed in the Cascades, we see substantial interannual variability in the spatial distribution of snow water equivalent (SWE). When examined in context with geology and landcover, this has important implications for groundwater recharge and land management practices. In a second study of low-flow in a glacierized watershed on Mt. Hood, Oregon, we find that glacier meltwater contributions make up 40-88% of streamflow during the low-flow season. As temperatures rise, the glacier augments streamflow but declining glacier size reduces the ability of the glacier to contribute to streamflow. Future projections show that ultimately, the declining glacier has a greater effect than augmented flow.