Evolution of coastal zone vulnerability to marine inundation in a global change context. Application to Languedoc Roussillon (France)

The coastal system is likely to suffer increasing costal risk in a global change context. Its management implies to consider those risks in a holistic approach of the different vulnerability components of the coastal zone, by improving knowledge of hazard and exposure as well as analyzing and quantifying present day and future territory vulnerability. The ANR/VMC2007/MISEEVA project (2008-2011) has applied this approach on Languedoc Roussillon region in France. MISEEVA approach relies on several scenarios for 2030 and 2100, in terms of meteorology (driver of coastal hazard), sea level rise, and also considering further trends in demography and economy, and possible adaption strategies Hazard has been modeled (SWAN, MARS and SURFWB), on the base of the presentday situation, sea level rise hypotheses, and existing or modeled data, of extreme meteorological driving f. It allowed to assess the possible surges ranges and map coastal zone exposure to: - a permanent inundation (considering sea level rise in 2030 and 2100, - a recurrent inundation (considering sea level rise and extreme tidal range) - an exceptional inundation (adding extreme storm surge to sea level rise and tidal range). In 2030, exposure will be comparable to present day exposure. In 2100, extreme condition will affect a larger zone. Present days social and economic components of the coastal zone have been analyzed in terms of vulnerability and potential damaging. Adaptation capacity was approached by public inquiries and interviews of stakeholders and policy makers, based on existing planning documents The knowledge of the present day system is then compared to the possible management strategies that could be chosen in the future, so to imagine what would be the evolution of vulnerability to marine inundation, in regards to these possible strategies

MULTIDECADAL SHORELINE VARIABILITY LINKED WITH ESTUARINE SANDBANK WELDING: THE NORTH MEDOC COAST, SOUTHWEST FRANCE

International audienc

Méthodes de calculs des potentiels et productibles associés aux énergies marines : études de cas en Manche-Atlantique

Face au développement des EMR (Energies Marines Renouvelables) ces dernières années et à la demande de collectivités publiques territoriales d'évaluer le potentiel énergétique de leur domaine côtier, il était nécessaire de se doter d'un outil intégré permettant de déterminer à l'échelle d'un site puis d'un territoire d'abord la ressource brute par type d'énergie, puis successivement le potentiel technique et technico-économique. Cela a conduit les équipes d'ARTELIA à mobiliser leurs spécialistes en hydraulique maritime et fluviale et les énergéticiens pour développer un outil dédié au calcul des productibles EMR. Dans cet objectif opérationnel, ARTELIA a mis en œuvre des actions R&D afin de disposer de l'état de l'art des méthodes de calculs en vigueur et des outils existants et mis en œuvre dans les autres pays européens pionniers du domaine et en particulier au Royaume-Uni (Atlas of UK Marine Renewables Energy Ressources, ABP Mer,) et aux Etats- Unis (travaux de l'EPRI -Electric Power Research Institute- notamment). L'outil a ensuite été développé et mis en œuvre successivement dans le cadre du calcul du potentiel EMR du domaine côtier de la Région Poitou-Charentes (Maître d'Ouvrage : Région Poitou-Charentes), puis à travers les missions d'études réalisées sur le potentiel hydrolien de Basse-Normandie (Maître d'Ouvrage : DREAL Basse-Normandie) et sur le potentiel EMR du littoral Aquitaine (Maître d'Ouvrage : Région Aquitaine - GIP Littoral Aquitain). L'outil permet successivement d'évaluer les gisements, potentiels techniques et technico-économiques des ressources EMR. Il a été appliqué à des études en lien avec des projets de fermes d'hydroliennes (offshore, en estuaires et rivières), houlomotrices (offshore, en zones littorale et côtière) et champs d'éoliennes offshore

Secular shoreline response to large-scale estuarine shoal migration and welding

International audienceThe 14.5-km North-Médoc coast, southwest France, is a high-energy mesoto macro-tidal environment adjacent to the largest estuary in Europe. Over the last centuries, this coastline has locally suffered periods of severe erosion, threatening coastal infrastructures and requiring the progressive implementation of coastal structures and, more recently, localized beach nourishments. This contribution combines 84 years (1937-2021) of shoreline data from various sources, 118 years (1903-2021) of shallow water bathymetric surveys and historical photographs. Results show that, averaged in both time and space, the coast eroded by-0.6 m/yr over the last 84 years, but with a large alongshore and temporal variability. Erosion is locally peaking at-5.2 m/yr, while accretion is restricted to a remote 2.5-km and locally peaks at 5.4 m/yr. A salient characteristic of shoreline evolution is the alternation of rapid erosion ( 20 m/yr) periods over relatively short intervals (≈ 10 years) and across limited alongshore distances (e.g. couple o

MISEEVA: set up of a transdisciplinary approach to assess vulnerability of the coastal zone to marine inundation at regional and local scale, within a global change context.

National audienc