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Title: Cyclical shoreline erosion: The impact of a jettied river mouth on the downdrift barrier island
Beaches and inlets throughout the U.S. have been stabilized for purposes of navigation, erosion mitigation, and economic resilience, commonly leading to changes in shoreline dynamics and downdrift erosion/accretion patterns. The developed beach of Plum Island, Massachusetts is highly dynamic, experiencing regular complex erosion / accretion patterns along much of the shoreline. We analyzed > 100 years of high-water line positions derived from satellite imagery, t-sheets, historical maps, and aerial photography. Unlike most beaches, the river-proximal sections of Plum Island are not uniformly retreating. Rather, the beach undergoes short-term erosion, followed by periods of accretion and return to a long-term mean stable shoreline position. These cycles occur over different time frames and in different segments of the beach, creating an ephemeral erosion ‘hotspot’ lasting as briefly as one year. The highly dynamic and spatially diverse nature of erosion along Plum Island provides insight into the complex nature of coupled inlet-beach dynamics over multiple timescales.  more » « less
Award ID(s):
1325430
PAR ID:
10046790
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the 11th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
Volume:
15
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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