Publications scientifiques

Intertidal communities dominated by canopy-forming brown algae (Phaeophyceae) usually prove to be highly productive systems, based on short-term measurements. However, long-term metabolism (primary production and respiration) is sensitive to several factors acting on different time scales (e.g. tidal cycle, seasonality), making its assessment challenging. Here, we used mathematical modelling to investigate the metabolism of a Fucus serratus-dominated community on daily and annual time scales.

Sandy beaches are highly dynamic environments buffering shores from storm waves and providing outstanding recreational services. Long-term beach monitoring programs are critical to test and improve shoreline, beach morphodynamics and storm impact models. However, these programs are relatively rare and mostly restricted to microtidal alongshore-uniform beaches. The present 16-year dataset contains 326 digital elevation models and their over 1.635 × 106 individual sand level measurements at the high-energy meso-macrotidal rip-channelled Truc Vert beach, southwest France.

Earthquakes affect near-surface permeability, however temporal permeability evolution quantification is challenging due to the scarcity of observations data. Using thirteen years of groundwater level observations, we highlight clear permeability variations induced by earthquakes in an aquifer and overlaying aquitard. Dynamic stresses, above a threshold value PGV > 0.5 cm s⁻¹, were mostly responsible for these variations. We develop a new model using earth tides responses of water levels between earthquakes.

Dans cet article, nous étudions l’évolution des cordons dunaires à l’est de Dunkerque, au nord de la France, sur une période s’étalant de novembre 2012 à février 2018. Elle se base sur l’analyse de relevés topographiques à haute fréquence, couplés à des données marégraphiques et de vent à la côte ainsi qu’à des enregistrements de vagues au large. Cette période d’étude a été marquée par plusieurs événements tempétueux dont les plus remarquables se sont produits au cours de l’hiver 2013/2014 ainsi qu’en janvier 2017 et en janvier 2018.

This study investigates the contribution of short-wave breaking to storm surges through a high-resolution hindcast of the sea state and storm surge associated with the extra-tropical storm Klaus. This storm made landfall in January 2009 in the Southern Bay of Biscay and produced the largest storm surges observed in this region over the last 20 years, with 1.70 m in the Arcachon Lagoon and 1.10 m in the Adour Estuary.

Giens double tombolo linking Giens island to the mainland is a unique geomorphological formation in the world. However, its existence has been threatened by coastal erosion, especially in the eastern part of this tombolo. The investigation of historical shoreline changes along the eastern Giens tombolo were carried out applying the integration of satellite remote sensing and geographic information system (GIS) techniques. Additionally, the combination of the Digital Shoreline Analysis System (DSAS) and linear regression method was used to predict the location of future shorelines.

Chronic flooding, occurring at high tides under calm weather conditions, is occasionally taking place today in the low-lying areas of the Petit-Cul-de-sac marin (Guadeloupe, West Indies, French Antilles). This area includes critical industrial, harbor and major economic infrastructures for the island. As sea level rises, concerns are growing regarding the possibility for repeated chronic flooding events, which would alter the operations at these critical coastal infrastructures without appropriate adaptation.

Dans les environnements côtiers, les interactions entre les processus morphodynamiques, océanographiques et anthropiques (agissant sur différentes échelles de temps) contrôlent l'évolution des systèmes littoraux. Cette thèse est axée sur une échelle de temps séculaire afin de déterminer l'influence non seulement des activités humaines, mais aussi l'impact du changement climatique.

We investigated the long-term changes of the principal tidal component M₂ over the North Atlantic coasts, from 1846 to 2018. We analysed 9 tide gauges with time series starting no later than 1920. The longest is Brest with 165 years of observations. We carefully processed the data, particularly to remove the 18.6-year nodal modulation. We found that M₂ variations are consistent at all the stations in the North East Atlantic (Newlyn, Brest, Cuxhaven), whereas some discrepancies appear in the North West Atlantic.