Department of Natural Resource Management Jimma, Jimma University, Jimma, Ethiopia.
Center for Environmental Science, Addis Ababa University, Addis Ababa, Ethiopia.
Environ Monit Assess. 2022 Feb 12;194(3):176. doi: 10.1007/s10661-022-09775-2.
Climate extremes are becoming more prevalent and hazardous as global climate change increases. The purpose of this study was to find out how often severe rainfall and temperature events occur, as well as the study area's spatial vulnerability indexes to extremes of both indices. Thirty years of daily rainfall and temperature data from 10 national meteorological stations were used. Four rainfall and eight temperature extremes were extracted using Climpact2 software tools. These variables were calculated for standardized anomaly and vulnerability indices and mapped using ArcMap. The results showed that the spatial variation of climatic extremes in the study area was significantly varied. Avery high rainfall (R95P) and extremely high rainfall (R99P) were widely experienced in the study area's west-south, but in the southeast, similar trends were rare. R95P had a statistically significant growing trend, but R99P did not. The warmest night temperature (TNx) event was widely observed in the east, southeast, and northwest, but the coldest night temperature (TNn) was only found in the eastern part. Extremely cold daytime temperatures (TXn) were more prevalent in the south and southeast of the study area, whereas extremely warm daytime temperatures (TXx) were more prevalent in the north. The number of dry spells (CDD), R95P, R99P, cold spells at night (TN10P), warm spells at night (TN90P), cold spells during the day (TX10P), and warm spells during the day (TX10P) frequency bell curves were skewed to the left side of the histogram. This suggests that the distribution of the variables was not symmetrical due to the fact that the negative anomaly frequencies of the variables were higher than the positive ones. The results of the spatial vulnerability study show that all provinces were vulnerable to the combined effects of climatic extremes, with scores ranging from 0.20 to 0.8, with none of them vulnerable and extremely vulnerable areas. Omo-Nada and Chora-Botor were particularly sensitive to climate change with an average score of 0.61. Only 12 of the 27 severe climate indexes were taken into account in this study, and the remaining 15 extreme indices will have to be investigated further.
随着全球气候变化的加剧，气候极端事件变得更加普遍和危险。本研究旨在了解极端降雨和温度事件的发生频率，以及研究区域对这两个指数极值的空间脆弱性指数。使用了来自 10 个国家气象站的 30 年逐日降雨和温度数据。使用 Climpact2 软件工具提取了 4 个降雨和 8 个温度极值。这些变量用于计算标准化异常值和脆弱性指数，并使用 ArcMap 进行了映射。结果表明，研究区域气候极值的空间变化差异显著。高降雨（R95P）和极高降雨（R99P）在研究区域的西部和南部广泛出现，但在东南部，类似的趋势很少见。R95P 呈显著增长趋势，但 R99P 没有。最暖夜温（TNx）事件在东部、东南部和西北部广泛出现，但最冷夜温（TNn）仅在东部出现。极冷日温（TXn）在研究区域的南部和东南部更为普遍，而极暖日温（TXx）在北部更为普遍。干旱日数（CDD）、R95P、R99P、夜间冷期（TN10P）、夜间暖期（TN90P）、日间冷期（TX10P）和日间暖期（TX10P）的频次钟形曲线向左偏。这表明由于变量的负异常频次高于正异常频次，变量的分布不对称。空间脆弱性研究的结果表明，所有省份都容易受到气候极端事件的综合影响，脆弱性得分在 0.20 到 0.8 之间，没有一个省份是脆弱或极度脆弱的。Omo-Nada 和 Chora-Botor 对气候变化特别敏感，平均得分为 0.61。本研究仅考虑了 27 个严重气候指标中的 12 个，其余 15 个极端指标还需要进一步研究。
