Integrated assessment of meteorological drought impacts on terrestrial water storage and vegetation dynamics in East Africa

Abstract Water is essential for life, and effective hydrological management is crucial for economic stability and quality of life. Poor water resource governance can lead to scarcity, displacement, or even fatal consequences. Hydrological conditions in East Africa are influenced by drivers such as demographic expansion, industrialization, droughts, and vegetation dynamics. This study explores how total water storage in the region responds to drought intensity and vegetation variability. To analyze drought conditions, the study employs CHIRPS satellite‐derived precipitation data (1982–2019) and calculates the 1‐ and 3‐month Standardized Precipitation Index (SPI) (2000–2019). Vegetation trends are assessed using MODIS‐derived Normalized Difference Vegetation Index (NDVI) over this same period. Variations in total water storage (2002–2019) are examined using Gravity Recovery and Climate Experiment (GRACE) and GRACE‐FO datasets. Results indicate increased drought severity from 2000 to 2005, followed by a decline until 2019. In 2002, approximately 7.6 × 10 5 km 2 of land was affected by drought, reducing to 4.2 × 10 5 km 2 by 2019. Concurrently, vegetation cover expanded from 1.73 × 10 6 km 2 (2002) to 2.06 × 10 6 km 2 (2019). GRACE‐derived terrestrial water storage anomalies exhibited substantial temporal variability throughout the study period, with prolonged storage deficits during major drought episodes and pronounced recovery during wetter climatic conditions. The observed TWSA patterns showed strong correspondence with variations in precipitation and vegetation dynamics across East Africa. Statistical analysis reveals a pronounced inverse relationship linking SPI and terrestrial water storage anomalies (TWSAs) ( r = −0.998) and a strong positive correlation between NDVI and TWSA ( r = +0.985). These statistical relationships demonstrate the coordinated response of terrestrial water storage and vegetation dynamics to regional precipitation variability. The findings highlight the imperative for sustainable land and water governance frameworks to counteract drought effects and strengthen hydrological resilience in East Africa.