Ethiopia is highly vulnerable to recurrent droughts and floods, requiring reliable rainfall data for agro-hydrological applications and early warning systems. Satellite-derived precipitation products are valuable for early warning of droughts and floods, addressing the challenges posed by scarce, unevenly distributed, and inconsistent rain gauge measurements, contingent upon their correctness being well established. Satellite rainfall products are effective solutions to address limited records and data problems, along with discrepancies regarding rain gauges. The primary difficulty with satellite rainfall retrieval techniques is their specificity to regions and times. Therefore, suitable satellite product selection is crucial. This study evaluates the performance of four satellite precipitation products, TAMSAT-V3.1, CHIRPS-V2, PERSIANN-CDR, and PERSIANN-CCS, over the Omo-Gibe basin. The products were assessed at daily, monthly, seasonal, and annual scales using volumetric, statistical, and categorical metrics and were further examined for drought and flood monitoring capability. At the daily scale, TAMSAT-V3.1 showed superior performance, although bias correction is required before replacing gauge data. At monthly to annual scales, CHIRPS-V2 outperformed the other products across statistical and volumetric metrics, making it the most suitable alternative for long-term agro-hydrological studies. For extreme event monitoring, PERSIANN-CDR demonstrated strong capability for drought detection, while CHIRPS-V2 performed better for flood assessment.
Burayu et al. (Wed,) studied this question.