Understanding rainfall distribution in space and time is crucial for sustainable water resource management and agricultural productivity. This study investigated the spatial distribution and temporal trends of rainfall in Amhara region using time series rainfall data of Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) for the period 1981–2017. Coefficient of variation, standardized anomaly index (SAI), precipitation concentration index (PCI) and seasonality index (SI) were used to evaluate rainfall variability and seasonality. Mann–Kendall's test was also employed for rainfall trend analysis. Results showed that the region has been experiencing variable rainfall events that cause droughts and floods over different years. SAI also witnessed the presence of inter-annual variability of rainfall with negative and positive anomalies in 59.46% and 40.54% of the analyzed years, respectively. PCI and SI results implied that the area had irregular and strong irregular rainfall distribution. Trend analysis results showed an overall increase in the annual and seasonal rainfall (except winter) during the study period. The information obtained from this study could serve as a proxy for rainfall variability and trend in the study area which might be used as input for decision-makers to take appropriate adaptive measures in various agricultural and water resources sectors.

了解时空上的降雨分布对于可持续水资源管理和农业生产力至关重要。这项研究使用了1981-2017年期间气候危害集团站内红外降水（CHIRPS）的时间序列降雨数据，调查了阿姆哈拉地区降雨的空间分布和时间趋势。利用变异系数，标准异常指数（SAI），降水集中指数（PCI）和季节性指数（SI）来评估降雨的变异性和季节性。曼恩·肯德尔的检验也用于降雨趋势分析。结果表明，该地区经历了不同的降雨事件，导致不同年份的干旱和洪水。SAI还见证了在分析年份分别有59.46％和40.54％的降雨出现年际变化，其中有负异常和正异常。PCI和SI的结果表明该地区降雨分布不规则且强。趋势分析结果显示，在研究期间，全年和季节性降雨（冬季除外）总体增加。从这项研究中获得的信息可以作为研究区域降雨变化和趋势的代理，可以用作决策者在各种农业和水资源部门采取适当适应措施的输入。趋势分析结果显示，在研究期间，全年和季节性降雨（冬季除外）总体增加。从这项研究中获得的信息可以作为研究区域降雨变化和趋势的代理，可以用作决策者在各种农业和水资源部门采取适当适应措施的输入。趋势分析结果显示，在研究期间，全年和季节性降雨（冬季除外）总体增加。从这项研究中获得的信息可以作为研究区域降雨变化和趋势的代理，可以用作决策者在各种农业和水资源部门采取适当适应措施的输入。