Drought and water scarcity pose a risk to the economy, particularly sectors where water is a crucial input to the production process. This paper describes integrated simulations of water shortages from a dynamic national water resource systems model with a static economic input-output (I-O) model to assess total drought risk to the economy. To quantify the economic risks of drought and water scarcity, the analysis: (a) integrates a large ensemble of simulated meteorological droughts, propagated through a national hydrological model and water resource systems model to simulate water availability from reservoirs and groundwater; (b) assesses implications of restrictions on water availability for multiple water user categories, representing natural and human contributions to water scarcity; (c) investigates how water shortages propagate into economy-wide direct and indirect impacts. The study focuses on England and Wales where the water supply system is considered under strain, with growing recognition of the economic risk of prolonged and widespread shortages. The direct Expected Annual Loss (EAL) to water users, averaged over an ensemble equivalent to 2800 years of synthetic daily weather, is estimated to be £11.7 million in the 2011 base-year. Accounting for indirect economic losses results in a total EAL of £30.2 million in 2011. The most severe event simulated results in a total loss of £1.4 billion in 2011, equivalent to 0.11% of GVA. The analysis provides a framework to assess what the economically efficient level of system reliability should be, and for deciding upon appropriate water management regulations and strategic investments.

中文翻译：

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基于风险的英格兰和威尔士干旱和缺水经济影响分析综合框架

干旱和缺水对经济构成风险，特别是在水是生产过程的关键投入的部门。本文描述了从动态国家水资源系统模型和静态经济投入产出 (IO) 模型对水资源短缺的综合模拟，以评估经济的总干旱风险。为了量化干旱和缺水的经济风险，分析：(a) 整合了大量模拟气象干旱，通过国家水文模型和水资源系统模型进行传播，以模拟水库和地下水的可用水量；(b) 评估限制对多种用水者的可用水量的影响，代表自然和人类对缺水的贡献；(c) 调查水资源短缺如何传播为整个经济的直接和间接影响。该研究的重点是英格兰和威尔士，那里的供水系统被认为处于压力之下，人们越来越认识到长期和普遍短缺的经济风险。用水者的直接预期年损失 (EAL) 平均相当于 2800 年的合成日常天气，在 2011 年基准年估计为 1170 万英镑。考虑到间接经济损失，2011 年的 EAL 总额为 3020 万英镑。最严重的事件模拟导致 2011 年的总损失为 14 亿英镑，相当于 GVA 的 0.11%。该分析提供了一个框架来评估系统可靠性的经济有效水平应该是什么，