CONSIDERING HOLISTIC COASTAL RESPONSE TO CLIMATE CHANGE AND MANAGEMENT SCENARIOS

Climate-change induced shoreline change can lead to the need for shoreline modifications (e.g., beach nourishment, seawalls, etc.) in an effort to protect coastal investments and habitats. In turn, these modifications can cause additional (anthropogenically-generated) shoreline change. Here, we explore the dynamics of this natural-human coupled system by working with The Nature Conservancy to investigate the potential collective, alongshore effects of management decisions made by independent stakeholders along the Eastern Shore of Virginia. To explore barrier island response to varying management actions under different climate change scenarios, we couple two existing shoreline change models. The Coastline Evolution Model (CEM) calculates alongshore sediment flux and can produce complex shoreline shapes (such as the Fishing Point spit at the southern end of Assateague Island) under high angle wave climates. These alongshore sediment flux calculations refine shoreline adjustments made by the Barrier Island Model which describes barrier island and inlet response to storms and sea-level rise Preliminary, uncoupled model experiments using CEM alone suggest that increases in wave climate asymmetry arising from changes in storm activity may extend the effects of human manipulation (i.e. nourishment) farther alongshore in the future. Additional initial results using the coupled model highlight the complex and varied responses of this natural-human system under a range of different climate change and management scenarios.