Comparison and evaluation of Multiple High-Resolution Precipitation Products and Their Implications for Water Resources Management in the Douala Sedimentary Basin (Cameroon)

Código

I-EBHE0051

Autores

Lambert NDONANG TCHIENGUE, Jean-Pierre BELL, Abdoukarim ALASSANE, Huguette Christiane EMVOUTOU, Albert Franklin TCHOKOUAHA, François MVONDO OWONO, Jules Remy NDAM NGOUPAYOU, Moussa BOUKARI, Serigne FAYE

Tema

WG 1.10: Hydrologic Design - Solutions & Communication

Resumo

High-resolution satellite precipitation data are increasingly sought after for numerous studies, particularly for water resources assessment. The accuracy of these satellite-derived estimates varies depending on the environment, making it essential to evaluate them before use. This study aims to assess four high-resolution satellite precipitation products (MSWEP v2.8, ARC v2, CHIRPS v2.0, and TAMSAT v3.1) using observed monthly precipitation data from 16 rain gauge stations in the Douala sedimentary basin in western Cameroon between 1980 and 1999. The pixel-to-point approach was used to compare monthly, seasonal, and annual satellite-estimated rainfall data with actual observations using commonly used statistical indices for this exercise. Despite the overall good performance of all tested products, only CHIRPS and TAMSAT reproduce the unimodal pattern of monthly precipitation in the basin, whereas MSWEP and ARC describe a bimodal pattern. ARC v2 significantly underestimates precipitation from March to October, while MSWEP overestimates it from January to April and underestimates it from June to August. The best monthly correlations were observed with CHIRPS and TAMSAT products, while at the annual scale, MSWEP and CHIRPS correlated better with observed data. CHIRPS and TAMSAT provided the best estimates of dry season cumulative precipitation, while MSWEP gave the best estimates of rainy season cumulative precipitation. The results of this study provide initial insights for selecting satellite precipitation products for various studies and for bias correction of these products in the Douala sedimentary basin.