Evaluating the performances of gridded satellite products in simulating the rainfall characteristics of Abay Basin, Ethiopia

Satellite Rainfall Estimates can be an alternative in data-scarce regions like Ethiopia. However, the reliability of Satellite Rainfall estimates need evaluation. In this study, the performance of Climate Hazard Group Infrared Precipitation with stations version 2.0 (CHIRPS v2.0), Multi-Source Weighted-Ensemble Precipitation version 2.8 (MSWEP v2.8) and Tropical Applications of Meteorology using Satellite and ground-based observations version 3.1 (TAMSAT v.3.1) products against observed data were evaluated. Student's t-test analysis at 5% level of significance revealed that TAMSAT v3.1 and CHIRPS v2.0 have not significance difference over tropical agro-ecological zone (AEZ), but over sub-tropical, temperate, and alpine AEZs the three rainfall products have significance difference in most temporal scales from daily to annual. The three rainfall products can detect rainfall occurrence over tropical, subtropical, temperate and alpine AEZs, but comparatively they showed low performance over alpine AEZ. CHIRPS v2.0 and MSWEP v2.8 were better to detect daily rainfall intensity of different intensity class over tropical AEZ. But, over sub-tropical AEZ, CHIRPS v2.0 was preferable to detect daily rainfall intensity of different classes. On the other hand, TAMSAT v3.1 takes the highest degree to detect different intensity class over temperate and alpine AEZs. But, TAMSAT v3.1 takes priority to detect daily rainfall total over temperate and alpine AEZs. In the case of detecting rainfall occurrence over temperate and alpine AEZs, both MSWEP v2.8 and TAMSAT v3.1 have equal performance. The findings of this study will play a noteworthy role to improve the study of rainfall characteristics by using the best-performing rainfall products for each AEZ for the specific temporal scales.