The spatio-temporal variability of groundwater storage cannot be well understood without proper groundwater monitoring schemes. Since 2002, the launch of the Gravity Recovery and Climate Experiment Satellite (GRACE) mission has served to monitor Groundwater Storage Anomaly (GWSA) and filled the observational data gap on a regional scale. This study aimed to estimate the spatio-temporal GWSA in Ethiopia using GRACE satellite data. GWSA was calculated by disaggregating GRACE estimation of Terrestrial Water Storage Anomaly (TWSA) using auxiliary soil moisture and surface runoff data obtained from the Global Land Data Assimilation System. GWSA was decomposed using the Seasonal-Trend decomposition method, LOESS (STL). The results depicted an increasing variability of TWSA and GWSA over various regions of the country. Ethiopia experienced an increase in TWSA (3.8 mm yr⁻¹) and GWSA (4.6 mm yr⁻¹) between the years 2003 and 2021, with GWSA contributing primarily to the TWSA. Greater contributions to the rise in groundwater storage come from the Rift Valley, Omo Gibe, Baro Akobo, and a portion of the Genale Dawa, Awash, and Wabi Shebelle Basins. Except for the lowlands (Northwestern, Northeastern and Southeastern), most regions showed an average increase in GWSA per annum at varying rates. Precipitation, temperature, and evapotranspiration have a significant influence on the spatial variability of GWSA. The impact of precipitation on GWSA reached its maximum after a 2-month lag (correlation coefficient (R) = 0.62). GRACE captured the seasonal GWSA of Ethiopia reasonably well and can be used as a guide for a more detailed evaluation of the groundwater potential.

如果没有适当的地下水监测计划，就无法很好地了解地下水储存的时空变化。自2002年以来，重力恢复与气候实验卫星（GRACE）任务的发射，致力于监测地下水储存异常（GWSA），填补了区域范围内的观测数据空白。本研究旨在利用 GRACE 卫星数据估算埃塞俄比亚的时空 GWSA。 GWSA 是通过使用从全球土地数据同化系统获得的辅助土壤湿度和地表径流数据分解陆地水储存异常 (TWSA) 的 GRACE 估计来计算的。 GWSA 使用季节趋势分解方法 LOESS (STL) 进行分解。结果表明，该国不同地区的 TWSA 和 GWSA 的变异性越来越大。 2003 年至 2021 年间，埃塞俄比亚的 TWSA (3.8 mm yr ^-1 ) 和 GWSA (4.6 mm yr ^-1 )有所增加，其中 GWSA 主要对 TWSA 做出了贡献。东非大裂谷、奥莫吉贝、巴罗阿科博以及杰纳莱达瓦盆地、阿瓦什盆地和瓦比谢贝尔盆地的部分地区对地下水储量的增加贡献更大。除低地（西北、东北和东南）外，大多数地区的 GWSA 每年平均以不同的速度增长。降水量、气温和蒸散量对GWSA的空间变化有显着影响。降水对GWSA的影响在滞后2个月后达到最大（相关系数（R）=0.62）。 GRACE 相当好地捕获了埃塞俄比亚的季节性 GWSA，可用作更详细评估地下水潜力的指南。