Publications scientifiques

The analysis of long-term tide gauge data collected in the Northeast Atlantic Ocean reveals that the seasonal cycle of mean sea level (hereafter MSL) exhibits amplitudes of up to 0.4 m. The position of MSL is of fundamental importance for many issues such as storm-induced flooding or the morphodynamics of shallow inlets, yet the underlying mechanisms are not fully understood. We characterize the seasonal cycle based on field observations complemented with a numerical hindcast.

Intertidal flats lying as a buffer zone between land and sea provide critical services including protection against storm surges and coastal flooding. These environments are characterized by a continuous redistribution of sediment and changes in topography. Sea level rise, anthropogenic pressures, and their related stressors have a considerable impact on these areas and are expected to put them under more stress; hence the increased need for frequent and updated topography maps.

The multipath signals of GNSS can act as a tide gauge via a technology called Global Navigation Satellite Systems multipath reflectometry (GNSS-MR), which is based on the relationship between multipath frequency and height to sea surface. In addition to the traditional frequency extraction method of Lomb–Scargle periodogram (LSP), wavelet analysis can be applied to extract instantaneous multipath frequencies of GPS L1, thus improving data utilization.

With 5853 km of coastlines facing the North Sea, the English Channel, the Atlantic Ocean and the Mediterranean Sea, France displays littoral zones exposed to a wide spectrum of wave climates, tidal ranges and storm surges. This study aims at characterizing in a systematic way sea level variations along the coasts of France. Wave climates are first characterized using state-of-the-art high resolution hindcasts validated against available observations from the national network CANDHIS.

Mayotte Island is characterized by a vast coral reef-lagoon complex comprising significant mangrove development and numerous pocket beaches nested between volcanic headlands. Since 2005, field experiments involving topographic surveys, observations and hydrodynamic measurements have been coupled with the analysis of aerial photographs (1950-2016) in order to improve understanding of the morphodynamic interactions between mangroves, beaches and the coral reefs.

Afin d'anticiper les dommages engendrés par les phénomènes de submersion marine et d'y faire face, CCR a développé un modèle spécifique à ce péril pour la France métropolitaine. Ce modèle présente deux volets : une modélisation déterministe permettant d'estimer le coût d'un événement quelques jours après sa survenance et une modélisation probabiliste permettant d'estimer l'exposition au risque de submersion marine.

The coastal zone is an important resource both socially and economically. Globally, coastal zones are under increasing threat from the effects of climate change, erosion and flooding. Understanding the mechanisms of coastal processes is key to the long term management and protection of the coastal zone and its resources. Sandbanks are large sedimentary bodies found on coastal shelves worldwide that protect nearby coastlines from the effects of erosion. This research aims to model the hydrodynamics and morphodynamics of the sandbanks in the southern bight of the North Sea, UK.

Fourteen years ago, the 26 December 2004 Indian Ocean tsunami demonstrated the destructional capability of tsunamis to the entire world. Since then, many research programs have been initiated to try to understand the phenomenon and its related hazards better and to improve the early warning systems for exposed coastal populations. Pacific Islands Countries and Territories (PICTs) are especially vulnerable to tsunamis. Amongst them, New Caledonia is a French overseas territory located in the Southwest Pacific and exposed to several tsunami sources.

The satellites of the Global Navigation Satellite System (GNSS) continuously broadcast L-band signals at about a 20-cm wavelength. Some signal-to-noise ratio (SNR) data received by off-shelf geodetic antennas contain the multipath information of the sea, and they have been demonstrated for use in retrieving sea levels; however, compared with conventional tide gauges, this GNSS multipath reflectometry (GNSS-MR) technique is limited in terms of both precision and sampling rate.