Decades of Change: Foredune Morphodynamics at Woonona Beach, Southeast Australia

Abstract Coastal foredunes serve as natural protective barriers, providing defence against storm impacts, erosion, and coastal inundation. In many locations they have undergone significant modifications, including sand mining, re-profiling, urban development, and interventions to enhance recreational amenities. While foredune morphology varies by location, this variation can reveal changes associated with storm events and modifications. This study examines foredune morphodynamics at Woonona-Bellambi Beach in southeastern Australia, using high-resolution three-dimensional LiDAR data to investigate changes across the foredune. The results reveal considerable spatial variability in foredune responses to, and recovery from, large-scale storm events and soft engineering modifications over annual to decadal timescales. Using recently released nearshore wave data, we extracted key storm events over the past decade for this beach which revealed spatially diverse patterns of erosion and recovery of the foredunes. These findings highlight the importance of high-resolution coastal investigations to improve understanding of local-to-regional responses and recovery processes across varying timescales. The insights gained can inform coastal modelling, planning, and management strategies.