Farther east, where dunes are generally smaller, sediment supply is limited, and the offshore physiography is different, the island is more vulnerable to storm-induced erosion and overwash. The eastern reach of Fire Island shows a pronounced landward translation of the dune–beach profile (verified through selected profiles), which in some instances show the shoreline of the most recent profile (2009) is nearly landward of the dune crestline of the oldest profile (1969) (Fig. 9e). The eastern reach is where Leatherman (1985) identified a number of former inlets over the last 300 years, and attributed landward
Refametinib of the eastern reach primarily to inlet processes transporting sediment to the backbarrier. According to his findings, nearly 85% of the island has been prone to inlet activity, resulting in island widening at former inlet locations and facilitating landward migration, particularly in the eastern reach. Our results show that average losses of dune crest elevation and landward shifts of the dune crest position are strongly correlated in undeveloped areas predicted to and in many cases observed to overwash during storm events. Limited volume and beach width changes in the eastern reach suggest that the overall profile configuration is conserved over the near-term as it moves landward (Fig. 9e). These results echo those proposed in the conceptual profile translation model by Davidson-Arnott (2005), which theorizes that dune volume is conserved as the
sediment eroded from the dune is carried landward, allowing the feature to largely retain its overall shape and appearance. Although the importance of inlets must be acknowledged, these results speak to the importance of overwash on morphology change and island-migration.
