Florence Toublanc

CNRS · LEGOS

Understanding estuarine sediment dynamics and particularly turbidity maximum dynamics is crucial for the management of these coastal systems. Various processes impact the formation, movement and structure of the turbidity maximum. Several studies have shown that tidal asymmetry and density gradients are responsible for the presence of this suspende...

Tidal asymmetry is a phenomenon that characterises estuarine hydrodynamics and has a strong impact on sediment dynamics. Extensive research has been dedicated to studying tidal dynamics in semidiurnal macrotidal estuaries, highlighting several general principles. The ratio of flood to ebb peak velocities and differences in ebb and flood durations a...

We study the Gironde River plume in the Bay of Biscay (North-East Atlantic) using a high resolution modeling approach of the estuary-mouth-shelf continuum. The Gironde River plume flows over a gently sloping shelf where semi-diurnal tides reach an amplitude of 1.3–1.5m on average; the Gironde River discharge undergoes a significant seasonal variabi...

We study the daily to interannual variability of the Red River plume in the Gulf of Tonkin from numerical simulations at high resolution over 6 years (2011–2016). Compared with observational data, the model results show good performance. To identify the plume, passive tracers are used in order to (1) help distinguish the freshwater coming from diff...

Satellite altimeters provide continuous information of the sea level variability and mesoscale processes for the global ocean. For estimating the sea level above the geoid and monitoring the full ocean dynamics from altimeters measurements, a key reference surface is needed: The Mean Dynamic Topography (MDT). However, in coastal areas, where, in si...

Downscaling physical processes from a large scale to a regional scale 3D model is a recurrent issue in coastal processes studies. The choice of boundary conditions will often greatly influence the solution within the 3D circulation model. In some regions, tides play a key role in coastal dynamics and must be accurately represented. The Bay of Bisc...

In the coastal ocean zones, satellite altimetry data processing and interpretation poses specific difficulties, due to the interaction of the radar signal with land topography, inaccuracies in some of the geophysical corrections and to the fast changes in the sea level. In order to optimize the completeness and the accuracy of the sea surface heigh...

A stereoscopic technique is developed in order to measure the sand-bed elevation in the swash zone at the wave time-scale. The present technique allows one to perform highly resolved measurements both in time and in space. An accuracy and a precision of less than 300μm and 600μm, respectively, are obtained in each direction. This technique has been...

The swash zone remains a difficult zone to account for in beach evolution models. One reason is the relative lack of data on the bed-shape evolution in this zone, especially data resolved on the short time scales of the incident waves, and this even in the laboratory. To this end, an optical method has been developed by the IMFT in Toulouse which i...