Environment, Commonwealth Scientific and Industrial Research Organization (CSIRO), Canberra, Australia.
PLoS One. 2023 Feb 6;18(2):e0280522. doi: 10.1371/journal.pone.0280522. eCollection 2023.
Droughts have severely affected Afghanistan over the last four decades, leading to critical food shortages where two-thirds of the country's population are in a food crisis. Long years of conflict have lowered the country's ability to deal with hazards such as drought which can rapidly escalate into disasters. Understanding the spatial and temporal distribution of droughts is needed to be able to respond effectively to disasters and plan for future occurrences. This study used Standardized Precipitation Evapotranspiration Index (SPEI) at monthly, seasonal and annual temporal scales to map the spatiotemporal change dynamics of drought characteristics (distribution, frequency, duration and severity) in Afghanistan. SPEI indices were mapped for river basins, disaggregated into 189 sub-catchments, using monthly precipitation and potential evapotranspiration derived from temperature station observations from 1980 to 2017. The results show these multi-dimensional drought characteristics vary along different years, change among sub-catchments, and differ across temporal scales. During the 38 years, the driest decade and period are 2000s and 1999-2022, respectively. The 2000-01 water year is the driest with the whole country experiencing 'severe' to 'extreme' drought, more than 53% (87 sub-catchments) suffering the worst drought in history, and about 58% (94 sub-catchments) having 'very frequent' drought (7 to 8 months) or 'extremely frequent' drought (9 to 10 months). The estimated seasonal duration and severity present significant variations across the study area and among the study period. The nation also suffers from recurring droughts with varying length and intensity in 2004, 2006, 2008 and most recently 2011. There is a trend towards increasing drought with longer duration and higher severity extending all over sub-catchments from southeast to north and central regions. These datasets and maps help to fill the knowledge gap on detailed sub-catchment scale meteorological drought characteristics in Afghanistan. The study findings improve our understanding of the influences of climate change on the drought dynamics and can guide catchment planning for reliable adaptation to and mitigation against future droughts.
在过去的四十年中，干旱严重影响了阿富汗，导致该国三分之二的人口面临严重的粮食短缺。多年的冲突降低了该国应对干旱等灾害的能力，而干旱可能迅速演变为灾害。了解干旱的时空分布情况对于能够有效应对灾害和规划未来的发生是必要的。本研究使用标准化降水蒸散指数（SPEI）在月、季和年时间尺度上，绘制阿富汗干旱特征（分布、频率、持续时间和严重程度）的时空变化动态图。使用 1980 年至 2017 年从温度站观测获得的每月降水和潜在蒸散量，对河流流域进行了 SPEI 指数制图，细分为 189 个子流域。结果表明，这些多维干旱特征在不同年份有所不同，在子流域之间发生变化，并且在时间尺度上有所不同。在 38 年期间，最干旱的十年和时期分别是 2000 年代和 1999-2022 年。2000-01 水年是最干旱的一年，全国经历了“严重”到“极端”干旱，超过 53%（87 个子流域）遭受了历史上最严重的干旱，约 58%（94 个子流域）经历了“非常频繁”（7 至 8 个月）或“极其频繁”（9 至 10 个月）干旱。估计的季节性持续时间和严重程度在整个研究区域和研究期间都有显著变化。该国还在 2004 年、2006 年、2008 年和最近的 2011 年遭受了持续时间和强度不同的反复干旱。从东南部到北部和中部地区，所有子流域的干旱持续时间更长，严重程度更高，呈现出逐渐加剧的趋势。这些数据集和地图有助于填补阿富汗详细子流域尺度气象干旱特征的知识空白。研究结果提高了我们对气候变化对干旱动态影响的理解，并可以指导集水区规划，以可靠地适应和缓解未来的干旱。
