ASSESSING SHORELINE CHANGE AND COASTAL HAZARDS FOR THE GEORGIA COAST

The Georgia coast has long been in need of a thorough and up-to-date assessment of the historical shoreline changes, sea-level rise, and other coastal geohazards that threaten the region along with developed areas. Likewise, there is also a great need for low-cost tools and techniques, based on sound science, for both coastal managers and researchers to rapidly evaluate these hazards to assist with various decisions. Currently, a project is underway that aims to not only fill in the data gaps of Georgia coastal geohazards, but also provide GIS-based and field tools and techniques for scientists and managers alike. The first phase of the project has mainly involved collecting shoreline data and building various software tools. A coast-wide shoreline database has been built spanning 1857 to 2006 from various sources from coastal shoreline survey maps to orthophotos. Although some historical shorelines were available from previous mapping projects from researchers and NOAA, new shorelines from these dates were re-digitized to ensure data quality. Along with building a shoreline database, GIS tools were built for ArcGIS and for R (www.r-project.org) to perform detailed shoreline change analyses. The focus of building the GIS tools has centered on allowing users to rapidly assess shoreline change trends through delivering results of each analysis in a series of spreadsheets, graphics, and maps. A toolbar has been created for ArcGIS that perform transect casting and captures historical shoreline positions along each transect. Outside of ArcGIS, new tools take advantage of the statistical power and graphics engine of R and perform the shoreline analysis while rendering spreadsheets, maps, and graphics. The second phase will focus on additional programming of tools/features and also concentrate on quantifying shoreline change rates and geohazards along the Georgia coast in order to fill in some of the long-standing data gaps. Overall, the project represents a progressive movement to map coastal geohazards in Georgia while bridging the gap between scientists and policy makers through sharing data, tools, and techniques.