Coastal erosion

Coastal erosion monitoring uses repeated observations to measure shoreline position change, beach and cliff retreat, sediment dynamics, and coastal land-loss trends.^[1][2]

Temporary storm-surge inundation is outside the topic unless it is tied to persistent morphology change.^[1][2]

Primary observations include repeated optical shoreline extraction, topographic or LiDAR surveys, SAR change evidence, and contextual sea-level or wave datasets.^[1][3]

Shoreline-change mapping and trend assessment are operational, with site uncertainty driven by tidal datum, waterline proxy selection, storm state, and cliff or beach morphology.^[2][3]

SAR backscatter change detection can detect coastline and coastal land-cover change under cloud and at night, InSAR can measure ground deformation contributing to relative shoreline retreat and coastal instability, and optical-SAR fusion combines optical shoreline evidence with SAR continuity for cloud-prone coasts.^[1][3]

Radar altimetry provides sea-level context for erosion risk and relative shoreline-change interpretation rather than direct shoreline mapping.^[1][3]