A PROCESS-ORIENTED SURVEY OF GLOBAL BARRIER ISLAND DEVELOPMENT WITH EMPHASIS ON THE U.S. NORTHEAST COAST

This study presents a summary of the development status of the world’s mixed-energy and wave-dominated coastal plain (non-deltaic) barrier islands and situates the U.S. northeast barrier islands in this context. We used Google Earth photographic imagery from 2015-2017 to quantify the amount and type of development within 300 m of the shoreline and compared those results to individual island lengths within barrier island chains. The USGS land-use classification scheme enabled us to categorize the predominant structure type for each island analyzed. Additionally, we highlight some of the unique challenges encountered in identifying and characterizing barrier islands using this technique. The results from this study showed that: (1) the U.S. east coast has the highest development density of mixed-energy (New Jersey = 62.5%) and wave-dominated (Florida = 73.2%) coastal plain barrier island chains in the world; (2) the south shore of Long Island is the fifth-most developed barrier chain globally (47.6%) and contains the most transportation, communication, and utility structures of all global barrier island chains (9.1%); (3) high-density, residential dwellings dominate the development (infrastructure) type along both mixed-energy and wave-dominated coastal plain barriers and comprise an average 19% of the world’s barrier island shorelines; and (4) mixed-energy and wave-dominated coastal plain barrier islands have comparable average percentages of developed shorelines globally (21.7% and 20.6%, respectively). The results from (4) enabled us to hypothesize that development density or land use type do not depend on or correlate with coastal processes (wave vs. tidal influence), i.e., coastal processes do not influence development type. Instead, site specific or regional factors dictate the density and type of development.