Alaska Coastal Change Viewer

The Coastal Change Viewer shows locations where relatively large areas of land have eroded away or sediment has been deposited. Results are based on satellite images taken between 1972 and 2014. While erosion is typically the greatest concern, areas with high sediment deposition can also create challenges, such as shifting river channels and narrowing lagoon or estuary entrances that can block travel.

The dataset is based on Landsat satellite imagery from 1972–2014, and provides information on change in areas down to the pixel size of 60 square meters (about 200 x 200 feet, roughly an acre). Therefore, the results capture changes—as seen from above—of 200 feet or more. Results are most reliable for areas larger than five hectares (a bit more than 12 acres, or roughly 14 pixels). This series of images was analyzed by the Western Alaska Landscape Conservation Cooperative and ABR, Inc. to document changes in features such as spits, barrier islands, coastal bluffs, estuaries, tidal guts, lagoons, rivers, and lowland lakes close to the coast.