Comparison and validation of eight satellite rainfall products over the rugged topography of Tekeze-Atbara Basin at different spatial and temporal scales

Abstract

16Satellite rainfall products are considered important options for acquiring rainfall estimates in the absence of ground measurements. However, estimates from these products need to be 18 validated as their accuracy can be affected by geographical position, topography, and climate, as well as by the algorithms used to derive rainfall from satellite measurements. Eight Results show thatCHIRPS, TRMM,and RFEv2 performed well and wereable to capture the 26 rainfall measured by rain gauges. The BIASand correlation of these products were within ±25% and >0.5over different time steps.The remaining products poorly performed at daily 28 time step with higher BIAS (up to ±200%) and lower correlation (<0.5). CMORPH, PERSIANN, and ARCv2 were relatively better while CMAP and GPCP performed poorly 30 (r<0.4) in all conditions. The overall performance of all products was lower in the mountainous areas of the basin with station elevation>2500 m.a.s.l. Compared to the 32 lowlands, the BIAS at highlands increased by 35% whilst the correlation dropped by 28%. Underestimation and overestimation of rainfall dominated in the mountainous and lowland 34 areas, respectively.CMORPH and TRMM overestimated while the remaining products underestimated the rainfall at all spatiotemporal scales. CMAP, ARC2, and GPCP estimates 36 were the most affected by large underestimation. Unlike in temporal scale, the performance of the products did not show a uniform pattern with respect to spatial scale.Their performance 38 improved from point to aerial comparisons in the lowlandswhereas it slightly reduced athighland areas. Poor performance in the highlands contributed to a slightly lower

Performance of the State-Of-The-Art Gridded Precipitation Products over Mountainous Terrain: A Regional Study over Austria

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Evaluation and Hydrologic Validation of Three Satellite-Based Precipitation Products in the Upper Catchment of the Red River Basin, China

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Validation of Three Satellite Precipitation Products in Two South-Western African Watersheds: Bandama (Ivory Coast) and Mono (Togo)

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