Mangrove forests can be an effective coastal defence in the Pearl River Delta, China

Abstract Coastal vegetation can reduce extreme water levels during storm events, but the controlling factors and processes in complex estuary or delta systems are still unclear. This limits an effective implementation of nature-based coastal defences mega-cities low-lying areas. Here we have numerically modelled how mangroves offer protection to large cities located Pearl River Delta (China), such as Guangzhou Shenzhen, strong typhoons, like Hato (2017). Water level attenuation by is conditions differences mangrove forests’ properties drive their function. The local (within-wetland) more with wide patches higher drag. Narrower provide non-local (upstream) if upper channels, design needs avoid amplification other