The Development of a Salt Marsh Migration Tool and Its Application in Long Island Sound

Given their location in the intertidal zone, coastal salt marshes will be one of the ecosystems first affected by sea level rise. As sea level rise increases, marshes will begin to migrate inland if surrounding topography and land use provide suitable habitat. The question remains whether or not this migration inland will provide enough new habitat to sustain current marsh area as the seaward edge of the marsh begins to become permanently inundated. This project created an ArcGIS tool using Python computer language that projects future salt marsh habitat under a variety of sea level rise and land use scenarios. The tool has several inputs including vegetation classifications, Digital Elevation Models (DEMs), current tidal conditions, and accretion rates. An object-oriented approach to image classification was used to develop the vegetation classifications and the DEMs were developed from LiDAR point clouds using the Geostastical Analyst in ArcGIS. This research expands on a presentation given at ASPRS 2009 in Baltimore, MD which used a preliminary version of the marsh migration tool to project future marsh habitat in eight study sites on the Connecticut coastline. This research has finished the development of the tool, making it more user-friendly and is currently expanding the geographic extent to include most of Long Island Sound.