基于多判据贝叶斯决策方法的城市洪水预警研究

The hazard risk of urban flooding and inundation has been increasingly pronounced under changing environmental conditions. It entails the development of a scientific, reliable and simple approach for issuing flood warning to ensure urban water safety, both the methodological significance and practical value of which are very meaningful. The objective of this project is to build an optimal decision-making system for aiding informed urban flood warning based on multi-source precipitation through following procedures: 1) quantitative evaluation of precipitation indexes; 2) identification of the watershed rainfall-runoff relationship and development of an urban hydrologic model to perform storm runoff simulation; 3) spatial analysis of precipitation information and selection of warning indexes; 4) development of multi-variable statistical forecasting model for storm peaks; 5) incorporation of multi-criteria analysis and Bayesian theory to make warning decisions. Through the case demonstration of Shenzhen city, a transparent and efficient operation pattern for issuing urban flood warning would be established, which is expected to enhance the confidence of warning users and stakeholders, and to increase the capacity of urban flood protection and disaster relief as well as social services and public safety.

变化环境条件下，城市洪涝灾害风险愈加突出，开展科学、可靠和简单的城市洪水预警决策研究对于保障城市水安全具有重要的方法学意义和实际应用价值。本研究将基于多源不同时空分辨率的降雨数据开展降雨特性的定量评估，系统辨识流域降雨径流响应关系并开发城市水文模型实现暴雨洪水模拟，在充分挖掘空间降雨信息的基础上筛选洪水预警的降雨指标并建立预警指标体系，进而通过构建各预警因子与洪峰流量的多变量统计预报模型，集成多判据分析和贝叶斯决策方法提出辅助城市洪水预警的优化决策方案。通过在深圳市的案例研究，辅助提供一种透明和高效的城市洪水预警模式，增强决策使用者或利益相关者的信心，提高城市防洪减灾能力，进一步支持社会公共安全服务。

变化环境条件下，城市洪涝灾害风险愈加突出，开展科学、可靠和简单的城市洪水预警决策研究对于保障城市水安全具有重要的方法学意义和实际应用价值。本项目在城市洪涝风险的理论与评价方面，基于Copula函数多元统计分析，结合暴雨事件发生强度与日期的相关性及其依赖性，精细化表征洪涝风险的特性，进而开发了模糊综合评价和贝叶斯网络的风险评价模型，识别和量化潜在的风险点及其灾害水平，支持城市洪涝风险区划与管控，可为区域洪涝防控策略提供重要参考。综合考虑复杂的城市下垫面特性，充分利用清华数字流域水文模型和SWMM的潜在优势，开发了具有较高可靠性、强适应性和拓展性好的城市水文模型，对不同降水条件和过程相应的城市水文、河流水质过程进行模拟和预测。基于机器学习降尺度技术的研发，预估了深圳市未来的气候变化动态，进而结合城市洪涝过程模拟，分析与评估了不同重现期降水、海平面上升和雨洪调控措施情景组合下城市的洪涝风险特征及其演化规律，为城市适应气候变化、建设韧性城市和保障水安全提供了评估工具和技术支撑。