Abstract This paper developed a GIS-based spatial multi-index model for large basin-scale flood risk assessment. In terms of the risk definition proposed by the IPCC, the flood risk in the Yangtze River Basin (YRB) was classified into indexes of hazard, vulnerability, and exposure. The model systematically accounts for various flood risk indicators related to the economic, social and ecological environment of the YRB. Using the robust data space analysis and processing capabilities of ArcGIS, these flood risk indicators were superimposed and analyzed to generate an integrated flood risk spatial distribution map for the YRB. The modeling results were verified reasonably well using observation data from the YRB floods in 1998, 2008, and 2016. We found that 24.90% of the study area was at very high and high risk in 1998, and the risk in these areas decreased to 15.95% and 17.61% in 2008 and 2016, respectively. We believe that the GIS-based spatial multi-index model can be applied to other areas where basin-scale flood risk assessment is desired and contribute to further scientific research on flood forecasting and mitigation.

中文翻译：

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基于GIS的长江流域洪水风险评估空间多指标模型

摘要 本文开发了一种基于GIS 的空间多指标模型，用于大流域尺度的洪水风险评估。根据IPCC提出的风险定义，长江流域（YRB）的洪水风险分为灾害、脆弱性和暴露度指标。该模型系统地考虑了与长江流域经济、社会和生态环境相关的各种洪水风险指标。利用ArcGIS强大的数据空间分析处理能力，将这些洪水风险指标进行叠加分析，生成长三角综合洪水风险空间分布图。利用 1998 年、2008 年和 2016 年长江流域洪水的观测数据，对建模结果进行了较好的验证。我们发现 1998 年研究区的 24.90% 处于极高和高风险，2008 年和 2016 年，这些领域的风险分别下降到 15.95% 和 17.61%。我们相信基于GIS的空间多指标模型可以应用于其他需要进行流域尺度洪水风险评估的地区，有助于进一步开展洪水预报和减灾的科学研究。