Landsat Coastal Mapping

Landsat coastal mapping uses the multispectral imagery of the Landsat satellites to track shoreline position and coastal change over time. The long, free Landsat archive, running since 1972 with 30 m optical bands and a 16-day revisit, lets analysts extract the instantaneous waterline and measure erosion, accretion, and inlet migration across decades. Band-ratio and water-index methods, often the green and near-infrared bands, separate water from land to sub-pixel precision; toolboxes such as CoastSat automate it across Landsat and Sentinel-2. The same imagery supports satellite-derived bathymetry in clear shallow water. It complements, but does not replace, survey-grade hydrography.