Efficiency of the summer monsoon in generating streamflow within a snow-dominated headwater basin of the Colorado River

This rain may buffer streamflow deficiencies caused by reductions in snow accumulation. Using a data-modeling framework, we explore the importance of monsoon rain in streamflow generation over historical conditions in an alpine basin.

Annually, monsoon rain contributes 18 7% water inputs and generates 10 6% streamflow. The bulk of rain supports evapotranspiration in lower subalpine forests. However, rains have the potential to produce appreciable streamflow at higher elevations where soil moisture storage, forest cover, and aridity are low and rebound late season streamflow 64 13% from simulated reductions in spring snowpack as a function of monsoon strength.