New Insights on Coastal Foredune Growth

New Insights on Coastal Foredune Growth: The Relative Contributions of Marine and Aeolian Processes

Cohn, Nicholas (Oregon State University)
Ruggiero, Peter (Oregon State University)
de Vries, S. (TU Delft Coastal Engineering)
Kaminsky, George M. (Washington State Department of Ecology)

2018

Coastal foredune growth is typically associated with aeolian sediment transport processes, while foredune erosion is associated with destructive marine processes. New data sets collected at a high energy, dissipative beach suggest that total water levels in the collision regime can cause dunes to accrete-requiring a paradigm shift away from considering collisional wave impacts as unconditionally erosional. From morphologic change data sets, it is estimated that marine processes explain between 9% and 38% of annual dune growth with aeolian processes accounting for the remaining 62% to 91%. The largest wind-driven dune growth occurs during the winter, in response to high wind velocities, but out of phase with summertime beach growth via intertidal sandbar welding. The lack of synchronization between maximum beach sediment supply and wind-driven dune growth indicates that aeolian transport at this site is primarily transport, rather than supply, limited, likely due to a lack of fetch limitations.

Beach
Coastal dunes
Intertidal sandbar
Morphodynamics
Progradation
Total water levels

http://resolver.tudelft.nl/uuid:d0003067-4e4a-4f58-b469-7455afb985fe

https://doi.org/10.1029/2018GL077836

2018-12-31

0094-8276

Geophysical Research Letters, 45 (10), 4965-4973

Institutional Repository

journal article

© 2018 Nicholas Cohn, Peter Ruggiero, S. de Vries, George M. Kaminsky