Zhang Yuqing, You Qinglong, Chen Changchun, Wang Huaijun, Ullah Safi, Shen Liucheng
School of Geography and Planning, Huaiyin Normal University, Huai'an 223300, China; Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China.
Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China.
Sci Total Environ. 2024 Mar 15;916:170133. doi: 10.1016/j.scitotenv.2024.170133. Epub 2024 Jan 17.
Flash droughts have gained considerable public attention due to the imminent threats they pose to food security, ecological safety, and human health. Currently, there has been little research exploring the projected changes in flash droughts and their association with compound meteorological extremes (CMEs). In this study, we applied the pentad-mean water deficit index to investigate the characteristics of flash droughts and their association with CMEs based on observational data and downscaled model simulations. Our analysis reveals an increasing trend in flash drought frequency in China based on historical observations and model simulations. Specifically, the proportion of flash drought frequency with a one-pentad onset time showed a consistent upward trend, with the southern parts of China experiencing a high average proportion during the historical period. Furthermore, the onset dates of the first (last) flash droughts during year are projected to shift earlier (later) in a warmer world. Flash droughts become significantly more frequent in the future, with a growth rate approximately 1.3 times higher in the high emission scenario than in the medium emission scenario. The frequency of flash droughts with a one-pentad onset time also exhibits a significant upward trend, indicating that flash droughts will occur more rapidly in the future. CMEs in southern regions of China were found to be more likely to trigger flash droughts in the historical period. The probability of CMEs triggering flash droughts is expected to increase with the magnitude of warming, particularly in the far-future under the high emissions scenario.
骤发干旱因其对粮食安全、生态安全和人类健康构成的紧迫威胁而备受公众关注。目前，很少有研究探讨骤发干旱的预测变化及其与复合气象极端事件（CMEs）的关联。在本研究中，我们应用五日平均水分亏缺指数，基于观测数据和降尺度模型模拟来研究骤发干旱的特征及其与CMEs的关联。我们的分析表明，基于历史观测和模型模拟，中国骤发干旱频率呈上升趋势。具体而言，以五日为起始时间的骤发干旱频率比例呈持续上升趋势，中国南部地区在历史时期的平均比例较高。此外，预计在气候变暖的情况下，一年中首次（末次）骤发干旱的起始日期将提前（推迟）。未来骤发干旱将显著增多，在高排放情景下的增长率约为中等排放情景下的1.3倍。以五日为起始时间的骤发干旱频率也呈现出显著的上升趋势，这表明未来骤发干旱将更快发生。在中国南方地区，历史时期的CMEs更有可能引发骤发干旱。预计CMEs引发骤发干旱的概率将随着变暖程度的增加而上升，特别是在高排放情景下的遥远未来。
