## 4 Discussion
### Implications and Scalability  
The PLEEZ case illustrates the application of the proposed framework. For an instructive generalization to other catchments, below, we further outline the recommended measures for the three ranks reported, customized for diverse decision-making contexts, such as authorities, the market, industries, the environment and the community (Figure 14). Figure 13: Error analysis results of RMAX3 between the future projected precipitation dataset (NEX-GDDP) and the historical satellite precipitation dataset (CHIRPS). Sub-figure (**h**) presents the error of the seven-year mean of RMAX3 in the RCP4.5 scenario, and sub-figure (**p**) presents the error for the RCP8.5 scenario. Each legend in the subfigure labels the range, mean and median of errors for all grids in the PLEEZ for the corresponding scenario. 1. The persistent challenges posed by frequent and severe damage in Rank 1 areas necessitate adequate resources and efforts from authorities, including the enhancement of the capability of infrastructure to withstand floods beyond design return periods, as well as the establishment of well-organized emergency planning and rescue actions. We suggest prioritizing the protection of wetland ecosystems over the development of highly vulnerable land types, while also promoting the universal expansion of flood insurance coverage in asset-intensive industrial and residential areas. The public sector should enhance the promptness and dissemination of disaster information, including weather prediction, early warning and loss estimation, while remaining vigilant to secondary hazards arising from floods. For communities with prior flood response experience, implementing a disaster reduction demonstration project to enhance community resilience is a feasible and promising initiative [82]. 2. Black swan-like major flood events are of particular concern in Rank 2 areas. A typical case is the megaflood that occurred in Zhengzhou, Henan Province, China, on 20 July 2021, which was triggered by a record-breaking extreme rainstorm (maximum hourly rainfall of 201.9 mm) and caused devastating damage. Due to the infrequency of inundation events and limited experience, risk management priority differs in Rank 2 areas. Authorities need to consider the addition or upgrading of drainage networks and the rational design of physical facilities capable of withstanding a 50-year flood or more extreme events. While inclusive insurance promotion may not be applicable, it is highly recommended to promote catastrophe insurance. Industry sectors should concentrate on the prediction and warning of extreme weather. In particular, industries should promptly respond and implement linkage measures to restrict social production and commuting activities upon issuance of a warning. Most importantly, there is an urgent need for extensive flood education and knowledge dissemination in communities to foster risk awareness among residents, which is currently lacking due to infrequent floods catching them off guard. Accordingly, a bottom-up risk management approach combined with socio-economic surveys aimed at improving the adaptive capacity of residents could be implemented, especially in developing countries [20]. 3. Rank 3 flood events resembling gray rihinos can be equally catastrophic once flooding is out of control. We call for a prudent development plan that emphasizes risk  
Figure 14: A hierarchical panel showing the general outline of management measures recommended for the three risk response ranks derived from the flood risk analysis framework. avoidance during urbanization and construction. Unplanned development changing land cover and use, coupled with climate change, would have negative effects on flood risk, as also supported by recent work [21; 83]. More land should be made available for mitigation purposes by reconverting farmland into lake, forests and natural floodplains, thus inducing its self-regulation of floods and restoration of erosion.