Using coastal models to estimate effects of sea level rise

Coastal numerical models have been used successfully for many marine analyses as well as for practical engineering applications. When a model is adjusted and verified for a particular coastal region, it may also be used for predicting potential impact due to sea level rise for that region. Applications include coastal flood risk analysis, alteration of long-term coastal sediment transport direction, and possible impact on the ecosystem due to changes in the coastal circulation pattern induced by the rise of mean sea level. This paper presents some examples for such applications including storm surge and near-shore tidal residual circulation patterns due to sea level rise. The paper presents a brief background discussion on the coastal hydrodynamic process. A three-dimensional numerical model of the China Sea is used as an example for the analyses. s from the numerical experiment indicate sea level rise may induce long-term changes in the near-shore tidal circulation patterns resulted from the alteration of residual currents. Rise in sea level would also cause more areas to be flooded due to storm surge. Existing sea walls and dikes designed for 100 year storm would be exposed to higher risks in the face of rising mean sea level. Modeling results would provide coastal designers and managers useful tools for developing vulnerability assessments and adaptation strategies. As an example, the paper presents some coastal flood risk analyses in which numerical modeling is combined with statistical typhoon landfall data over the China Sea coast.