Similar to S1 Data, for 2051–2075.

Rainfall variability and change are critical drivers of food production in tropical regions. This study analyzed rainfall trends and variability in the drylands of Wolaita Zone (DLWZ), southern Ethiopia. It used observed rainfall data (1990–2022) and projections for 2026–2075 under two shared socioeconomic pathways (SSP2-4.5 and SSP5-8.5). Rainfall variability was assessed using the coefficient of variation, while trends were examined with the modified Mann–Kendall test and Sen’s slope. Results show extremely high (>30%) to high (20–30%) seasonal and inter-annual variability during 1990–2022, with decreasing rainfall trends except for winter, which showed a non-significant increase. Projections indicate medium (10–20%) to high variability in annual rainfall and high to extremely high variability in seasonal rainfall. Significant decreases are expected in spring rainfall, while summer and winter rainfall are projected to increase, particularly in 2051–2075. These findings suggest that persistent variability and declining rainfall during critical seasons may intensify risks to agricultural production in southern Ethiopia. The dataset provides a valuable basis for future studies on the impacts of rainfall change on crop and livestock systems.降雨变异性与变化是热带地区粮食生产的关键驱动因子。本研究针对埃塞俄比亚南部沃莱塔区旱地（DLWZ）的降雨趋势与变异性展开分析，采用了1990–2022年的实测降雨数据，以及两种共享社会经济路径（Shared Socioeconomic Pathways，SSP2-4.5与SSP5-8.5）下2026–2075年的降雨预估数据。本研究通过变异系数（coefficient of variation）评估降雨变异性，并借助修正曼-肯德尔检验（modified Mann–Kendall test）与森斜率（Sen’s slope）分析降雨趋势。结果显示，1990–2022年期间，研究区季内与年际降雨变异性处于极高（>30%）至较高（20%–30%）区间；除冬季降雨呈不显著增长外，其余季节降雨均呈现下降趋势。降雨预估结果表明，年降雨量变异性处于中等（10%–20%）至较高区间，而季降雨量变异性则处于较高至极高区间。预计春季降雨量将出现显著下降，而夏季与冬季降雨量则呈增长趋势，尤其在2051–2075年时段更为明显。上述研究结果表明，关键生育期持续存在的降雨变异性与降雨量下降，可能加剧埃塞俄比亚南部地区农业生产面临的风险。本数据集可为后续开展降雨变化对作物与畜牧系统影响的相关研究提供重要支撑。