Analysis of climate variability and trends frequently takes place at large scale. For agricultural applications, however, highly localized climate conditions can be critically important. This certainly applies to tropical highland regions, where dissected topography and convectively dominated precipitation processes can lead to strong variability in both mean climate conditions and year-to-year climate variability. This study examines recent climate variability and trends (1981–2016) on Choke Mountain, located in the western Ethiopian Highlands. Through analysis of precipitation and temperature records at monitored locations, we explore observed variability in climate patterns and trends across sites and seasons. The lens for our spatial analysis is the agroecosystem (AES), defined on the basis of prevailing climate and cropping systems, which currently serve as the foundation for climate adaptation planning in the region. We find that interannual temperature variability is greatest in the hottest, driest AES, and is most pronounced in the dry season. All AES warmed significantly in all seasons over the analysis period, but the magnitude of trend was greatest in high elevation AES. Precipitation variability was also large across AES, with largest interannual variability found in the dry season. This season is frequently excluded in climate analyses, but it is a critical harvest time and irrigation period. Trends in rainfall anomaly and precipitation concentration index are less clear, but there is a tendency towards drying and increasing irregularity of rainfall. Interestingly, we find little association between the El Niño Southern Oscillation (ENSO) and temperature or precipitation variability at our study sites. This suggests that even though ENSO is a widely recognized driver of large-scale rainfall variability in the region, its impacts are highly spatially variable. This has implications for applying ENSO-based precipitation outlooks to agricultural management decisions. Farmer interviews reveal that local perceptions of climate variability and trends are generally consistent with the objective observations.

通常对气候变异性和趋势进行大规模分析。但是，对于农业应用而言，高度局部化的气候条件可能至关重要。这当然适用于热带高地地区，那里的地形和对流占优势的降水过程会导致平均气候条件和逐年气候变化的强烈变化。这项研究调查了位于埃塞俄比亚西部高地的扼流山最近的气候变异性和趋势（1981–2016）。通过分析监测地点的降水和温度记录，我们探索观测到的气候模式的变异性以及站点和季节之间的趋势。我们进行空间分析的依据是农业生态系统（AES），它是根据当时的气候和种植系统而定义的，目前是该地区气候适应规划的基础。我们发现，在最热，最干燥的AES中，年际温度变化最大，而在旱季最明显。在分析期间，所有季节的所有AES均显着变暖，但高海拔AES的趋势幅度最大。整个AES的降水变化也很大，在旱季发现最大的年际变化。气候分析通常不包括该季节，但这是关键的收获时间和灌溉期。降雨异常和降水集中指数的趋势不太清楚，但是有干燥的趋势和降雨不规则性增加。有趣的是 在我们的研究地点，我们发现厄尔尼诺南方涛动（ENSO）与温度或降水变化之间几乎没有关联。这表明，尽管ENSO是该地区大规模降雨变化的公认驱动因素，但其影响在空间上是高度可变的。这对于将基于ENSO的降水前景应用于农业管理决策具有影响。农民访谈显示，当地对气候变异性和趋势的认识通常与客观观察结果一致。