High-resolution simulation of coastal flooding under extreme storm tides and sea level rise: A case study of Macau.

This article focuses on the development and application of the Ocean University of China – Coastal Urban Flood Model (OUC-CUFM), a high-resolution urban flood model based on two-dimensional nonlinear Navier–Stokes shallow water equations, designed to simulate storm tide inundation at street level in coastal cities. Using Macau as a case study, the model was calibrated and validated with data from Typhoons Hato (2017) and Mangkhut (2018), demonstrating accurate predictions of flood depth, extent, and timing. The study further applied the model to project flood hazards under sea level rise (SLR) scenarios of 0.5 m and 1.0 m, revealing significant increases in inundation area, volume, duration, and velocity, particularly in low-lying urban zones. The OUC-CUFM incorporates detailed representations of buildings, levees, and land use types, making it a valuable tool for urban flood risk assessment, hazard mapping, and infrastructure planning in densely built coastal environments facing climate change impacts.