Quantifying the relative contribution of the climate and direct human impacts on mean annual streamflow in the contiguous United States

Both climate change and human activities are known to have induced changes to hydrology. Consequently, quantifying the net impact of human contribution to the streamflow change is a challenge. In this paper, a decomposition method based on the Budyko hypothesis is used to quantify the climate (i.e., precipitation and potential evaporation change) and direct human impact on mean annual streamflow (MAS) for 413 watersheds in the contiguous United States. The data for annual precipitation, runoff, and potential evaporation are obtained from the international Model Parameter Estimation Experiment (MOPEX), which is often assumed to only include gauges unaffected by human interferences. The data are split into two…

• UD
  U.S. Department of Energy
• B
  Battelle
• UO
  University of Central Florida
• PN
  Pacific Northwest National Laboratory