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Submarine dune dynamics is studied in the context of a macrotidal continental shelf subjected to the swell action. Off Dieppe (Eastern English Channel), the gravelly-sand seabed is moulded by dunes and sand banks, and characterized by gradients in hydrodynamics, morphologies and sediment grain-size, which are studied according to various spatial (grain, dune, gradient) and temporal scales (moment, semi-diurnal and semi-lunar tidal cycles, year, several decades). Multivaried analysis, carried out on morphological, sedimentary and hydrodynamic parameters, showed that the sediment grain-size and sediment availability are the main controlling factors of the morphology and the dynamics of the dunes. The inter-dune variability is more pronounced than the intra-dune variability, when sediment and benthic characteristics are considered. Over a 56-year period, repeated bathymetric surveys show a decrease in dune migration rates when observation periods are longer, implying a significant and frequent oscillation of dune displacements. On periods longer than one year, the dune movement concern the whole sedimentary bedform and the direction coincides with that of the residual of tide. On the semi-diurnal to the semi-lunar tidal cycle timescales, dune displacements are often confined in the crest zone. It seems that sedimentary budget is reorganized along the dune field and not at the scale of each single dune. Sediment flux calculations (bedload, non-uniform sediment) show that waves, even weak, can reverse residual sedimentary transport direction and increase the amount of transported sediments (from 10 to 100 times more for significant wave height of 1.5 m, and up to 1000 times more for annual waves). VHR seismic measurements make it possible to visualize dune internal architecture. 0.5 to 4 ° dipping discontinuities (second- order) constitute the dune master-bedding and their periodicity of formation is estimated to be inclued between 4 and 18 years. These periodicities are similar to those observed from the wavelet analysis carried out on the chronicles of tide and wave time-series recorded in the study area, and on a NAO index chronicle. Preserved second-order discontinuities are interpreted as erosive surfaces due to a temporary inversion of dune migration, caused by exceptional storm events. Their formation seems to obliterate several second-order discontinuities formed previously during weaker wave events. The medium term climatic fluctuations, which control the variability of the storm events, are presented as being the main factor influencing dune dynamics on the long term. This study of an exceptional dune field in the Eastern English Channel, according to various spatial and temporal scales, allows to put forward new interpretations as for modalities of the mobility of submarine dunes. These results can answer applied concerns, such as maritime safety, the hiding objects.