Short-term intertidal bar mobility on a ridge-and-runnel beach, Merlimont, northern France

Digital elevation models and topographic profiles of a beach with intertidal bar and trough (ridge‐and‐runnel) morphology in Merlimont, northern France, were analysed in order to assess patterns of cross‐shore and longshore intertidal bar mobility. The beach exhibited a pronounced dual bar–trough sys...

Full description

Saved in:
Bibliographic Details
Published in:Earth surface processes and landforms 2005-01, Vol.30 (1), p.81-93
Main Authors: Anthony, E. J., Levoy, F., Monfort, D., Degryse-Kulkarni, C.
Format: Article
Language:English
Subjects:
beach morphodynamics
Bgi / Prodig
Coastal geomorphology
Earth Sciences
Geomorphology
intertidal bars and troughs
longshore currents
Physical geography
ridge-and-runnel beach
Sciences of the Universe
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Digital elevation models and topographic profiles of a beach with intertidal bar and trough (ridge‐and‐runnel) morphology in Merlimont, northern France, were analysed in order to assess patterns of cross‐shore and longshore intertidal bar mobility. The beach exhibited a pronounced dual bar–trough system that showed cross‐shore stationarity. The bars and troughs were, however, characterized by significant longshore advection of sand under the influence of suspension by waves and transport by strong tide‐ and wind‐driven longshore currents. Profile changes were due in part to the longshore migration of medium‐sized bedforms. The potential for cross‐shore bar migration appears to be mitigated by the large size of the two bars relative to incident wave energy, which is modulated by high vertical tidal excursion rates on this beach due to the large tidal range (mean spring tidal range = 8·3 m). Cross‐shore bar migration is also probably hindered by the well‐entrenched troughs which are maintained by channelled high‐energy intertidal flows generated by swash bores and by tidal discharge and drainage. The longshore migration of intertidal bars affecting Merlimont beach is embedded in a regional coastal sand transport pathway involving tidal and wind‐forced northward residual flows affecting the rectilinear northern French coast in the eastern English Channel. Copyright © 2004 John Wiley & Sons, Ltd.
ISSN:0197-9337
1096-9837
DOI:10.1002/esp.1129