Methodology for Validation on Satellite Precipitation Time Series Estimations in Catumbela Basin, Angola

2. Group of Hydrology and Water Resources, Faculty of Engineering, Agostinho Neto University, Angola

Abstract: Both satellite-retrieved rain gauge data have been commonly used in basin-scale hydrological applications. As opposed to satellites, which provide common error-prone retrieval as well as spatially regular observations, rain gauges present precise measurements that are normally unevenly distributed in space. In hydrological studies, precipitation is considered as the most prominent input in basin-scale water balance, and, thus, there is a demand to do a comparative evaluation of gauge-based and satellite-based data. This study employs both prevailing satellite products Tropical Rainfall Measuring Mission (TRMM 3B43) and PERSIANN, and quality-controlled rain gauge data for examining the discrepancies and consistency between them at different scales. TRMM and rain gauge products were accessible in the Catumbela Basin, Angola, from 1998 to 2019 (PERSIAN: 1998-2019). The results attained depicted that normally the performance of TRMM products increases due to an increase in the increasing spatial scale; on both monthly and annual scales, the accuracy is highest for TRMM 3B43, with PERSIANN. Normally TRMM satellite products overestimate precipitation due to a raised degree of estimation in light and moderate rain cases and frequency.