Coastal zones are constantly changing in response to meteorological and hydrodynamic conditions. Water levels associated with storms, coupled with wind-driven waves, can significantly reshape coastal and deltaic geomorphology. Conversely, coastal wetlands attenuate waves, surge, and currents. These interactions have profound implications for ecosystem function and human infrastructure. This article discusses how predictive numerical models and remote-sensing techniques can advance understanding of the dominant process response (and feedbacks) of coastal and deltaic systems to a wide range of natural and anthropogenic changes. Remote-sensing techniques can provide valuable information at large spatial scales (10¹–10³ km²) and at temporal scales ranging from days to decades that can be used to parameterize and validate numerical models, especially in regions such as the Mekong Delta where in situ data are sparse. Applications to the Mekong Delta system illuminate how modeling tools can reliably predict and describe system dynamics. Numerical modeling supported by remote-sensing information is an effective approach for evaluating and examining restoration and protection strategies, and for ameliorating the effects of climate change, natural hazards, and anthropogenic alterations to coastal ecosystems and human communities.

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