Compound flood effects, challenges and solutions: Lessons toward climate-resilient Chinese coastal cities

Compound flood events by storm-enhanced intensive rainfall and surges on coastal and inland surface water flooding are increasingly exacerbated, causing significant impacts in coastal cities. In light of climate change and the rapid urbanisation process, future flood risks and consequences of compound floods are growing. Among global coastal cities, Chinese coastal cities face substantial challenges reflected in recent flood impacts and damages. Here we investigate the previous compound flood sources, impacts, consequences, challenges, and more importantly the response measures from the case of Chinese coastal cities by integrating the media sources and governmental literature analyses. We have found that, during the last decade (the 2010s-2020s), the Chinese Central Government (CCG) and Municipality authorities have co-produced good practices to reduce compound flood impacts accordingly via efficient emergency responses, technological services (e.g., via mobile phones and apps), and improvement of the blue-green (i.e., via "Sponge City Program") and adopted with the engineering measures standard in the coastal urban environment. For the advancement in the next 10 years and beyond, we encourage the governments to transform the Chinese coastal cities by further implementing the "Sponge", Nature-Based Solutions mixed with communication technologies, engineering and meteorological perspectives. These practices are the keys to improving future Chinese coastal flood resilience in terms of reducing the risk and consequences of the compound flood generated by sea-level rise, storm surges and intensive rainstorms under climate uncertainties.