Citizen science monitoring of beach and dune erosion during Hurricane Fiona

Abstract

ABSTRACT Hurricane Fiona made landfall as an extra-tropical storm along the north shore of Prince Edward Island (PEI), Canada, in October 2022. The state of the beach and dune immediately before and after the storm was captured through the Coastie citizen science beach and dune photo monitoring initiative, as part of the global CoastSnap Community Beach Monitoring program. Coastie monitoring sites within Prince Edward Island National Park (PEINP) revealed extensive dune scarping, capturing a 12–17 m retreat of the foredune at Brackley and Cavendish Beaches. Using foredune scarp and post-storm shoreline positions, volumetric losses between 28 and 76 m3 m−1 are estimated from profiles located within the first 150 m of the stations. The average horizontal position of the projected foredune scarp position was within 2.8 m of the position identified from high accuracy unoccupied aerial system (UAS) surveys, corresponding to a mean absolute difference of 15.3 m3 m−1 or 45.3% for dune volume changes estimated from the images. Continued monitoring will yield further improvements to the volume loss estimation methodology, and insight on the timing and mechanisms of beach and dune recovery.