Department of Civil Engineering, The University of Hong Kong, Hong Kong, China; State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai, China.
Department of Civil Engineering, The University of Hong Kong, Hong Kong, China.
Sci Total Environ. 2018 Mar;616-617:363-375. doi: 10.1016/j.scitotenv.2017.10.321. Epub 2017 Nov 7.
Drought is a complex natural hazard that may have destructive damages on societal properties and even lives. Generally, socioeconomic drought occurs when water resources systems cannot meet water demand, mainly due to a weather-related shortfall in water supply. This study aims to propose a new method, a heuristic method, and a new index, the socioeconomic drought index (SEDI), for identifying and evaluating socioeconomic drought events on different severity levels (i.e., slight, moderate, severe, and extreme) in the context of climate change. First, the minimum in-stream water requirement (MWR) is determined through synthetically evaluating the requirements of water quality, ecology, navigation, and water supply. Second, according to the monthly water deficit calculated as the monthly streamflow data minus the MWR, the drought month can be identified. Third, according to the cumulative water deficit calculated from the monthly water deficit, drought duration (i.e., the number of continuous drought months) and water shortage (i.e., the largest cumulative water deficit during the drought period) can be detected. Fourth, the SEDI value of each socioeconomic drought event can be calculated through integrating the impacts of water shortage and drought duration. To evaluate the applicability of the new method and new index, this study examines the drought events in the East River basin in South China, and the impact of a multi-year reservoir (i.e., the Xinfengjiang Reservoir) in this basin on drought analysis is also investigated. The historical and future streamflow of this basin is simulated using a hydrologic model, Variable Infiltration Capacity (VIC) model. For historical and future drought analysis, the proposed new method and index are feasible to identify socioeconomic drought events. The results show that a number of socioeconomic drought events (including some extreme ones) may occur in future, and the appropriate reservoir operation can significantly ease such situation.
干旱是一种复杂的自然灾害，可能对社会财产甚至生命造成破坏性的破坏。一般来说，当水资源系统无法满足水需求时，就会发生社会经济干旱，主要是由于与天气相关的供水短缺。本研究旨在提出一种新方法、一种启发式方法和一个新指数，即社会经济干旱指数（SEDI），用于在气候变化背景下识别和评估不同严重程度（即轻度、中度、重度和极端）的社会经济干旱事件。首先，通过综合评估水质、生态、航运和供水要求来确定最小河流径流量（MWR）。其次，根据逐月计算的水量亏缺（即逐月径流量减去 MWR），可以识别干旱月份。第三，根据逐月水量亏缺计算的累积水量亏缺，可以检测干旱持续时间（即连续干旱月份的数量）和缺水（即干旱期间最大累积水量亏缺）。第四，通过综合考虑缺水和干旱持续时间的影响，可以计算每个社会经济干旱事件的 SEDI 值。为了评估新方法和新指数的适用性，本研究考察了中国南方东江流域的干旱事件，并研究了该流域的一座多年调节水库（即新丰江水库）对干旱分析的影响。该流域的历史和未来流量使用水文模型（变量渗透能力模型（VIC））进行模拟。对于历史和未来的干旱分析，所提出的新方法和指数是可行的，可以识别社会经济干旱事件。结果表明，未来可能会发生一些社会经济干旱事件（包括一些极端事件），而适当的水库运行可以显著缓解这种情况。
