TY  - JOUR
AU  - Yoshe, Agegnehu Kitanbo
PY  - 2026
DA  - 2026/02/10
TI  - Characterization of Drought Severity Using GRACE and TerraClimate Dataset in the Rift Valley Basin, Ethiopia
JO  - Advances in Environmental and Engineering Research
SP  - 003
VL  - 07
IS  - 01
AB  - Characterizing drought severity using GRACE and TerraClimate datasets is globally important because it enables consistent, large-scale monitoring of both surface and subsurface water availability across data-scarce regions. This integrated perspective supports improved drought assessment, climate change impact analysis, and informed water-resource management worldwide. The Ethiopian Rift Valley has experienced recurrent hydrological drought hazards, posing serious threats to water availability, agricultural productivity, ecosystem stability, and the socio-economic well-being of local communities. The region’s high spatial and temporal variability of rainfall has contributed to recurrent and severe drought episodes, emphasizing the need for reliable drought monitoring and assessment tools. This study utilizes GRACE (Gravity Recovery and Climate Experiment)-derived terrestrial water storage (TWS) data to develop a GRACE-based drought index (GRDI/WSDI) for the Rift Valley Basin from 2002 to 2016. GRACE data provide a unique integrated measure of hydrological components, including surface water, soil moisture, and groundwater, enabling the detection of droughts that conventional meteorological indices may not capture. The study also evaluates conventional drought indices, including SPI, SPEI, SRI, ESI, and EDDI, across multiple accumulation periods (3, 6, 9, 12, 18, 24, 36, and 48 months) to examine temporal drought characteristics such as severity, duration, and cumulative deficit. The GRACE-based analysis revealed extreme drought events in 2013 and 2014, with total drought indices of 10.3 and 15.9, respectively, indicating prolonged and severe water deficits. Additionally, significant drought periods were consistently identified during 2002-2003, 2007-2012, and 2014-2016 across multiple indices. Comparative analysis demonstrated strong agreement among SPI, SPEI, SRI, and ESI, while GRDI/WSDI uniquely captured large-scale water storage deficits, including groundwater depletion. The EDDI, which reflect atmospheric evaporative demand, displayed complementary drought signals, highlighting the importance of multiple indices for comprehensive drought assessment. The findings indicate that droughts in the Rift Valley Basin have become increasingly frequent, prolonged, and severe in recent decades, consistent with regional climate variability and global climate change trends. This study underscores the value of integrating satellite-based hydrological observations with conventional meteorological and remote sensing indices to improve drought monitoring, early warning systems, and water resources management. The results provide actionable insights for policymakers, water resource managers, and stakeholders to implement effective drought mitigation strategies, optimize water allocation, and enhance resilience to climate-induced water stress in one of Ethiopia’s most vulnerable basins.
SN  - 2766-6190
UR  - https://doi.org/10.21926/aeer.2601003
DO  - 10.21926/aeer.2601003
ID  - Yoshe2026
ER  -