Watersheds of the Future Could Mirror a Variable Climate
Precipitation, water yield from forests, and forest growth and productivity generally increase from west to east across the United States. Shifts in temperature and precipitation associated with climate change may not necessarily alter these general west-to-east trends, but U.S. Forest Service and university researchers do anticipate great variability in how watersheds respond to increasing temperatures and the extreme precipitation and drought events expected in the future. For a recently published study, researchers compared past (1979-2007) and future (2031-2060) watershed dynamics using a combination of two computer models—the Water Supply Stress Index Model, a tool that predicts water and carbon balances from the watershed to national scale, and the Weather Research and Forecasting (WRF) Model, which simulates atmospheric conditions and allowed researchers to “downscale” global climate change data to make them relevant to U.S. regional areas. “When we looked at the U.S. as a whole, we found that future precipitation and temperature could follow a similar west-to-east pattern as the 1979 to 2007 baseline period,” says Eastern Threat Center research hydrologist Ge Sun, a co-author of the study. “But for each watershed, these two climate variables will likely increase or decrease by different magnitudes in the future, leading to different responses in terms of water yield and ecosystem productivity.” Read more in CompassLive...