Morphodynamics of intertidal dune field in a mixed wave-tide environment: Case of Baie de Somme in Eastern English Channel

Understanding the response of the intertidal dunes to the varying hydrodynamic conditions in mixed wave-tide environments is of high complexity. Field measurement is one of the most useful approaches to investigate the dune dynamics at different time (semi-diurnal and lunar cycles) and spatial (dunes and associated superimposed bedforms) scales. High-resolution laser scanner data for five successive surveys over a full neap-spring cycle (27 January – 9 February 2014), together with hydrodynamic measurements, have been explored to investigate the morphodynamics of dunes, their superimposed bedforms and their migration in a mixed wave-tide environment (case of the Baie de Somme, Eastern of the English Channel), by the use of a stochastic-physical coupling approach. The dunes are ~12 m wavelength, 0.4 height and oriented orthogonally to the shoreline with angles varying between - 45° and + 45° corresponding to clockwise and counter-clockwise changes, respectively.