Zhu Ziyang, Duan Weili, Zou Shan, Zeng Zhenzhong, Chen Yaning, Feng Meiqing, Qin Jingxiu, Liu Yongchang
State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Total Environ. 2024 Apr 15;921:170913. doi: 10.1016/j.scitotenv.2024.170913. Epub 2024 Feb 12.
Meteorological drought is a crucial driver of various types of droughts; thus, identifying the spatiotemporal characteristics of meteorological drought at the basin scale has implications for ecological and water resource security. However, differences in drought characteristics between river basins have not been clearly elucidated. In this study, we identify and compare meteorological drought events in 34 major river basins worldwide using a three-dimensional drought-clustering algorithm based on the standardised precipitation evapotranspiration index on a 12-month scale from 1901 to 2021. Despite synchronous increases in precipitation and potential evapotranspiration (PET), with precipitation increasing by more than three times the PET, 47 % (16/34) of the basins showed a tendency towards drought in over half their basin areas. Drought events occurred frequently, with more than half identified as short-term droughts (lasting less than or equal to three months). Small basins had a larger drought impact area, with major drought events often originating from the basin boundaries and migrating towards the basin centre. Meteorological droughts were driven by changes in sea surface temperature (SST), especially the El Niño Southern Oscillation (ENSO) or other climate indices. Anomalies in SST and atmospheric circulation caused by ENSO events may have led to altered climate patterns in different basins, resulting in drought events. These results provide important insights into the characteristics and mechanisms of meteorological droughts in different river basins worldwide.
气象干旱是各类干旱的关键驱动因素；因此，识别流域尺度上气象干旱的时空特征对生态和水资源安全具有重要意义。然而，不同流域干旱特征的差异尚未得到明确阐释。在本研究中，我们使用基于标准化降水蒸散指数的三维干旱聚类算法，在1901年至2021年的12个月尺度上，识别并比较了全球34个主要流域的气象干旱事件。尽管降水和潜在蒸散（PET）同步增加，且降水增加幅度超过PET的三倍，但47%（16/34）的流域在其一半以上的流域面积上呈现出干旱趋势。干旱事件频繁发生，超过一半的干旱事件被确定为短期干旱（持续时间小于或等于三个月）。小流域的干旱影响面积更大，主要干旱事件往往起源于流域边界并向流域中心移动。气象干旱受海面温度（SST）变化驱动，尤其是厄尔尼诺南方涛动（ENSO）或其他气候指数。ENSO事件引起的SST和大气环流异常可能导致不同流域气候模式改变，从而引发干旱事件。这些结果为全球不同流域气象干旱的特征和机制提供了重要见解。
