Deep groundwater mediates streamflow response to climate warming and will provide a major source of summer streamflow for the western U.S. in the future
Prior efforts to model streamflow trends, and hence the availability of water, under future climate scenarios in the Western United States focused on snowpack dynamics. But snowpack is only one source of water. Station scientists found that groundwater dynamics exert a comparable, or even larger, control on future streamflow regimes than does snowpack. Different landscapes will have widely different responses to the same climate warming. Regions of the West with primarily groundwater sources will continue to have streamflow under climate warming, in contrast to areas served exclusively by snowpack, such as the southern Sierras in California. However, these same groundwater regions display maximum sensitivity to warming climate and will lose a significant proportion of their flow volumes, perhaps leading to unanticipated consequences for water quantity and aquatic habitat.
These findings are being directly incorporated into long-range management plans and strategies under development by the Eugene Water and Electric Board and other public water and energy utilities. The peer-reviewed papers reporting these results have resulted in invitations to address international scientific audiences and to serve on high-profile scientific committees considering the impacts of climate change on the quantity and quality of water.
Forest Service Partners