Declining precipitation in the mountains of the Pacific Northwest
Location
Eccles Conference Center
Event Website
http://water.usu.edu
Start Date
4-1-2014 11:00 AM
End Date
4-1-2014 11:20 AM
Description
Declining flows in Pacific Northwest streams have been noted by several authors, but the causality has been unclear, because precipitation data at COOP weather stations in the region have shown little to no change. Closer examination, however, reveals that COOP stations may not reflect precipitation in the mountains, implying that observed streamflow declines are likely driven by mountain precipitation declines. Decreases in winter westerlies across the region from 1950-2012 are hypothesized to have driven these declines, as winter (Nov-Mar) westerlies are strongly correlated to high elevation precipitation but weakly correlated with low elevation precipitation. Climate projections show weakened westerlies across the region under enhanced greenhouse forcing, highlighting an additional stressor relevant for climate change impacts on hydrology.
Declining precipitation in the mountains of the Pacific Northwest
Eccles Conference Center
Declining flows in Pacific Northwest streams have been noted by several authors, but the causality has been unclear, because precipitation data at COOP weather stations in the region have shown little to no change. Closer examination, however, reveals that COOP stations may not reflect precipitation in the mountains, implying that observed streamflow declines are likely driven by mountain precipitation declines. Decreases in winter westerlies across the region from 1950-2012 are hypothesized to have driven these declines, as winter (Nov-Mar) westerlies are strongly correlated to high elevation precipitation but weakly correlated with low elevation precipitation. Climate projections show weakened westerlies across the region under enhanced greenhouse forcing, highlighting an additional stressor relevant for climate change impacts on hydrology.
https://digitalcommons.usu.edu/runoff/2014/2014Abstracts/23