Numerical and Analytical Investigation of Satellite Precipitation Error Propagation in Hydrologic Simulations

The overarching goal of the research described in this dissertation is to understand the hydrologic implications of error propagation from satellite precipitation products to hydrologic simulations. The complex interaction between precipitation error and corresponding hydrologic response is examined following a numerical- and an analytical-based method. The application of a hydrologic model forced by various satellite precipitation products is adopted as the numerical-based framework that was used to identify the properties of error propagation with respect to a number of factors (e.g. basin scale, seasonality, severity of rainfall and flow). Results show better consistency between gauges for events occurred over larger scale basins during warm season months that are associated with moderate intensity of rain and flow rate. In addition to the numerical investigation, an analytical framework is developed to decompose the error propagation into space-time components. This essentially allows to assess the relative contribution of the different processes of catchment flood response on error propagation. It is shown that error in timing of flood event is equally attributed to due to error in runoff generation and routing time. Error in hydrograph shape is mainly controlled by the error in the variability of runoff generation time while error in flood volume is predominantly controlled by the error in rainfall volume. Overall, these investigations provide important information for the hydrologic modelers to choose the appropriate precipitation products for the hydrologic-related practice. It also serves as a guidance for the product developers on the designs of more advance retrieval algorithms