Estimating impacts of future rainfall change on Stream flow and sediment load in Lower Yazoo River Watershed Using BASINS-HSPF-CAT modeling system
Climate change over the past several decades has resulted in shifting rainfall pattern and modifying rainfall intensity, which has, in turn, exacerbated stream flow and sediment load and imposed uncertainties to these processes. This study projected impacts of potential future rainfall variations on stream flow and sediment load from the Lower Yazoo River Watershed (LYRW) in Mississippi using the BASINS (Better Assessment Science Integrating Point and Nonpoint Sources)-HSPF (Hydrological Simulation Program-FORTRAN)-CAT (Climate Assessment Tool) modeling system. Several simulation scenarios were performed to investigate impacts of different future rainfall rates on stream discharge and sediment load in the LYRW. Results showed that over a ten-year simulation period, an increase in the rainfall rate by 10% and 20%, respectively, resulted in increasing discharge by 8.1% and 7.4% as well as in increasing sediment load by 1.1 and 1.2 times. A potential future wet climate had discernable impacts on stream flow and sediment load in the LYRW. The BASINS-HSPF-CAT modeling system is a useful tool to modify historical rainfall data to project future rainfall impacts on watershed hydrological processes and sediment load due to climate change.