Coastlines are dynamic landscapes that respond to a variety of meteorlogical and hydrodynamic forces at a range of spatio-temporal scales. Short-term hazards such as storms, which result in extreme coastal erosion, flooding, and infrastructure damage, are particularly challenging problems to prepare for and typically require billions of dollars for restoration and recovery efforts. Long-term hazards such as sea-level rise create challenges that aggregate in time and threaten large-scale communities and low-lying critical infrastructure. Sand resources are at a premium, and their effective management is critical to the long-term resilience of our Nation’s coastlines. CHL advances a range of measurement and modeling expertise, tools, and databases to characterize the relevant coastal forcing climatology. To quantify the coastal response, CHL develops advanced field measurement techniques and modeling/analysis tools for coastal sediment transport and morphology response to support integrated coastal zone management and resilient coastlines. To support the design of engineering measures to manage coastal risk related to navigation, flooding, and coastal erosion, CHL develops and executes physical and numerical modeling of coastal protection strucuture response.