Awash River basin (ARB) as a system is in a state of continuous change that requires successive studies to discern the changes or trends of climatic elements through time due to climate change/variability, and other socio-economical developmental activities in the basin. The livelihood of communities in the ARB is primarily based on rainfall-dependent agriculture. Effects of rainfall anomalies such as reduction of agricultural productivity, water scarcity, and food insecurity are becoming more prevalent in this area. In recent years, ARB has been experiencing more frequent rainfall anomalies that change-point detection test and trend analyses of basin rainfall associated with sea surface temperature is crucial in providing guidance to improve agricultural productivity in ARB. Change-point detection tests such as Pettit’s, the von Neumann ratio (VNR), Buishand’s range (BR) and standard normal homogeneity (SNH) plus trend analysis Mann-Kendall (MK) test of rainfall and temperature data from 29 meteorological stations in the ARB were carried out from 1986 to 2016. A significant increasing trend of annual and seasonal temperature was found. The temperature change-points for the annual and major rainy season (MRS) were detected in 2001, while for the minor rainy season (mRS) in 1997. A significant decreasing trend, shift, and high variability of rainfall were detected in the downstream part of the ARB. The BR and SNH results showed that the mRS rainfall change-point was in 1998, with a subsequent mean annual decrease of 52.5 mm. The increase (decrease) of rainfall in the annual and MRS was attributable to La Niña (El Niño) events. The significant decreasing trend and change-point of rainfall in the mRS was attributable to the steady warming of the Indian and Atlantic Oceans, local warming, and La Niña events. With this knowledge of the current trends and change-point for rainfall and temperature in the ARB, it is therefore essential that appropriate integrated water management and water-harvesting technologies are established, especially in the downstream areas. Moreover, early detection of El Niño episodes would provide invaluable warning of impending rainfall anomalies in the ARB and would enable better preparations to mitigate its negative effects.

阿瓦什河流域 (ARB) 作为一个系统处于持续变化的状态，需要进行连续研究，以识别由于气候变化/变异性以及流域内其他社会经济发展活动而导致的气候要素随时间的变化或趋势。ARB 社区的生计主要以依赖降雨的农业为基础。降雨异常的影响，例如农业生产力下降、水资源短缺和粮食不安全，在该地区变得越来越普遍。近年来，ARB经历了更频繁的降雨异常，与海面温度相关的盆地降雨变化点检测测试和趋势分析对于为ARB提高农业生产力提供指导至关重要。变点检测测试，例如 Pettit's，对1986年至2016年ARB 29个气象站的降雨和温度数据进行冯诺依曼比(VNR)、布山德极差(BR)和标准正态均匀性(SNH)加趋势分析曼-肯德尔(MK)检验。发现年和季节性温度有显着增加的趋势。2001年检测到年和大雨季（MRS）的温度变化点，1997年检测到小雨季（mRS）。在下游检测到显着的下降趋势和变化，降雨量变化很大的 ARB。BR和SNH结果表明，mRS降雨变化点在1998年，随后年均下降52.5 mm。年降雨量和 MRS 降雨量的增加（减少）归因于拉尼娜（厄尔尼诺）现象。mRS降雨量的显着下降趋势和变化点归因于印度洋和大西洋持续变暖、局地变暖和拉尼娜事件。了解了 ARB 中降雨和温度的当前趋势和变化点，因此必须建立适当的综合水资源管理和集水技术，尤其是在下游地区。此外，厄尔尼诺现象的早期检测将为 ARB 即将出现的降雨异常提供宝贵的警告，并有助于更好地准备减轻其负面影响。了解了 ARB 中降雨和温度的当前趋势和变化点，因此必须建立适当的综合水资源管理和集水技术，尤其是在下游地区。此外，厄尔尼诺现象的早期检测将为 ARB 即将出现的降雨异常提供宝贵的警告，并有助于更好地准备减轻其负面影响。了解了 ARB 中降雨和温度的当前趋势和变化点，因此必须建立适当的综合水资源管理和集水技术，尤其是在下游地区。此外，厄尔尼诺现象的早期检测将为 ARB 即将出现的降雨异常提供宝贵的警告，并有助于更好地准备减轻其负面影响。