Hydrological response to climate change in the Black Hills of South Dakota, USA

The hydrological response due to potential CO2-forced climate change in the Black Hills of South Dakota was investigated using modelling techniques that include variations to atmospheric CO2, temperature, and precipitation. The soil and Water Assessment Tool (SWAT) was used to model the 427 km(2) Spring Creek basin hydrology and simulate the impact of potential climate change. As expected, modelling results of precipitation and temperature change demonstrated that increased temperature caused a decrease in water yield while increased precipitation caused an increase in water yield. Increased CO2 and precipitation caused the largest increase in yield. Modelling results of increased atmospheric CO2 indicate that average annual water yield increased by 16%. The increase is attributed to a suppression of transpiration processes due to increased level of atmospheric CO2. Simulation results demonstrate that increased concentrations of atmospheric CO2 act to dampen water yield loss due to the effects of increased temperature or decreased precipitation alone.