MODELING UPPER CITARUM WATERSHED HYDROLOGY USING SWAT+ AND GSMAP PRECIPITATION DATA

Abstract

Hydrological modeling is a vital tool for understanding the complexities of the hydrological cycle. The Soil and Water Assessment Tool Plus (SWAT+), a semi-distributed hydrological model, simulates processes across various spatial and temporal scales. With advancements in hydrological modeling, integrating satellite data has become essential to address input data variability and improve analysis accuracy. This study evaluates the performance of satellite data as a primary input for SWAT+ in hydrological modeling. The model was validated against observed streamflow data, with performance assessed using Nash-Sutcliffe Efficiency (NSE), Percent Bias (PBIAS), and flow duration curves (FDC). Despite the model successfully capturing general seasonal patterns of wet and dry streamflow at a monthly scale, metric results showed suboptimal NSE and PBIAS values, reflecting significant discrepancies between simulated and observed data. This study highlights the potential of satellite data to mitigate data challenges in hydrological modeling while emphasizing the need to refine input data quality and parameterization to improve performance. The findings provide a foundation for further integrating remote sensing data into SWAT+ applications.