The shorelines for 2013, 2014 and 2015 were created from high-resolution dGPS coastal surveys. Displayed in this app are three shoreline types. Bluff edge position was captured by surveyors walking as close to the edge as possible with a dGPS unit. Waterline positions were captured by a surveyor driving an ATV along the instantaneous waterline, meaning the boundary between water and land at the time of survey, with a special rig that placed the dGPS antenna directly over this waterline. Coastal Engineering positions were captured by surveyors walking along the top of sand berms with a dGPS unit. Survey were completed during the summer months from June to August.
The position of shorelines have relatively small errors associated with each. These errors stem from accuracy of dGPS units, antenna placement, surveyor error, and high water line position (for waterline surveys). The BAID Team conducted an analysis of these uncertainties by year, coastline and shoreline type. Total shoreline position uncertainties are: +/- 0.588m for Beaufort Bluff Edge; +/- 2.011m for Chukchi Bluff Edge; +/- 0.079m for Coastal Engineering; +/- 1.05 for Waterlines. These errors are smaller than for most studies of coastal change in Alaska.
Recent shoreline changes are useful in studying drivers of coastal erosion.