Spatio-temporal variability of currents and sediment fluxes over a dune field in the Dover Strait

Abstract

A one month field campaing featuring two spring-neap tide cycles and three strong storms has been performed in a dune area located in the central part of the Dover Strait. A total of eight different meteorological regimes have been distinguished. The analysis of the currents measurements at five locations in the area shows that the eight meteorological regimes induce very different current responses at the bottom. The residual tidal currents exhibit a significant spatial variability both in direction and in intensity also observed in the total residual currents for high tidal range regimes. During strong wind periods however the wind-induced currents which are more uniform in space dominate the tidal currents. During high tidal range periods, the sediment flux are high. The residual sediment transport however was shown to depend on tidal and non-tidal currents amplitude and direction giving rise to a significant temporal variability in sediment fluxes amplitudes and directions and to different spatial sediment transport patterns over the area.