VANISHING ISLANDS: USING ARCGIS TO CALCULATE HISTORIC RATES OF BARRIER ISLAND MIGRATION ALONG THE DELAWARE BAY COAST OF NEW JERSEY

Our aim is to examine the fetch limited barrier islands along the Delaware Bay coast of New Jersey to establish rates of migration and other geomorphic changes. Even though these barrier isalnds protect vast swaths of sensitive intertidal biomes, little is known about their specific response to sea level rise. Estuarine barrier islands provide critical habitat for myriad organisms, such as nesting piping plovers and breeding horseshoe crabs. They also act as natural buffers, diminishing physical energy from waves and currents, protecting delicate salt marsh ecosystems. The continued viability of barrier islands is threatened in the face of rising seas and coastal erosion. While this peril is well known qualitatively, it is necessary to understand these processes quantitatively in order to anticipate the effects of sea level rise on the estuary’s fragile wetlands biomes. We will calculate shoreline change through time-series analysis of historic records, including ground surveys, National Oceanographic Service charts, aerial photographs, and satellite imagery. A transect-based approach will be used to analyze shoreline change along coast-perpendicular transects. The Digital Shoreline Analysis System, developed by the U.S. Geological Survey, will be used with ESRI ArcGIS to compute shoreline rates of change. The resulting product will show rates of historic shoreline change along the study area.