QUANTIFYING STORM IMPACTS ON SANDY BEACHES USING A DETERMINISTIC/THEORETICAL STORM IMPACT FACTOR MODEL WITH AN APPLICATION ALONG THE VIRGINIA COAST

This research presents a new theoretical model that quantifies the impact of storms on sandy beaches using the cumulative impact of the timing between successive storms and a storm erosion potential index. The weighting scheme utilized by the model is able to represent the synergistic effect of a current storm and storms that have preceded it by incorporating a dependence of the past (“memory”) and the present into calculation of an erosion potential. Applying this model to long-term water-level data from a Virginia tide gauge showed that the greatest erosion potential occurred not during some of the largest storms to have impacted the mid-Atlantic coast (e.g., the Ash Wednesday nor’easter, 1962, the “Perfect Storm,” 1991, or Hurricane Sandy, 2012), but rather during an especially stormy winter season in which 13 storms occurred in succession between November and May 2010. Additionally, this method uncovered an acceleration (not detectable by single storm impact analyses) toward increased storm erosion potential for Virginia beginning c. 1980. We expect this model to have utility in many areas of the coastal sciences and engineering including incorporation into more holistic process-response models, quantifying erosion potential at other locations and managing coastal ecosystems.