Sensitivity of Streamflow Simulation to Changes in Climatic Inputs

Sensitivity of streamflow simulations to changes in temperature and precipitation were evaluated for a small basin (A ≡ 53 km²) characterized by low evapotranspiration and high conversion of precipitation into streamflow. Using a calibrated HSPF model, such sensitivities were studied for temperature increases up to 4° C and precipitation fluctuations of ± 10%. Temperature increases barely affected annual streamflow, led to larger and earlier winter runoff when precipitation was stored in the snowpack, and increased winter/spring streamflow peaks. Effects of precipitation fluctuations were more direct - annual and seasonal streamflow fluctuations were directly proportional to precipitation changes and monthly peaks increased about twice as much as precipitation.