Les élus locaux face aux nouveaux défis de la gestion des risques côtiers d’érosion et submersion en france : le cas de Plonévez-les-Flots.

National audienc

Les élus locaux face aux nouveaux défis de la gestion des risques côtiers d’érosion et submersion en france : le cas de Plonévez-les-Flots.

National audienc

Systemic vulnerability of coastal territories to erosion and marine flooding: A conceptual and methodological approach applied to Brittany (France)

International audienceThe attractiveness of the coasts tends to increase their exposure to erosion and marine flooding risks. This exposure is exacerbated by the effects of climate change, in particular sea level rise. To contribute to strategic thinking on the vulnerability of coastal areas, it is essential to develop, share and collectively maintain relevant knowledge on risks. This article will present the thinking behind the setting up of a coastal risks observatory in Brittany, a region located in north-western France. It relies on a conceptual approach to systemic vulnerability based on four components: hazards, assets, management, and social representations. Hazards and assets underpin the notion of risk and tend to increase the vulnerability, management tends to mitigate it, and representations can play a part in increasing or decreasing it depending on the context. To understand and analyze this system of vulnerability, our approach is based on the generation of a set of 62 indicators combined into different types of indices. A web-GIS interface was developed to navigate through and map this system of vulnerability. The difficulties associated with this type of synthetic approach will be discussed, whether they are related to data availability, to the links between scientific research and operational territorial management requirements, or to an understanding of the dynamics of all of the vulnerability components and their interactions. Ultimately, the approach developed has been successful in mobilising scientific and operational stakeholders around the co-construction of a diagnosis of territories with regard to their vulnerability to coastal risks

Can CoastAppli (a citizen science smartphone app) improve monitoring and understanding of coastal hazards to support coastal management?

International audienceCoastal erosion and flooding remain unknown hazards and elected officials and coastal managers may have difficulty discussing these phenomena with the general public. However, a better knowledge of the evolution of these hazards, through citizen science, can help raise awareness of coastal dynamics among the general public and thus meet the current and future challenges of coastal management. During the OSIRISC project (2016-2020), funded by the Fondation de France, coastal managers wanted to set up a smartphone app to save time during their field surveys, while allowing citizens to perform some measurements. How to create a citizen science app on coastal hazards that is reliable and intelligible and that guarantees the sustainable support of participants (professionals and non professionals)? Within the framework of the observatory of coastal risks in Brittany (OSIRISC), protocols for measuring hazards 1) with common tools (benchmarks such as the size of one's finger, qualitative data with photographs) or cheap tools (tape measure, laser distance meter...), 2) applicable to all types of coasts (beach, cliff…) have been co-designed with the managers and integrated into the android app called CoastAppli. Co-funded by EUR ISblue (the interdisciplinary graduate school for the blue planet), Sea-Eu and Interreg AGEO projects, CoastAppli is currently being tested for 6 months (until April 2022) in the municipality of Guissény (Brittany, France) by grade school students, coastal managers and citizens. The feedback from this test will allow us to know: i) the reliability of the measurements; ii) whether the app meets the expectations of the coastal managers by saving time for data collection in the field; iii) the app ability to be understood and educative; iv) the sustainability of the commitment of the citizens. These results are essential to validate the application before a future deployment that is intended in Brittany, then in France and beyond

Studies of "cliff erosion" and "coastal flooding" hazards (France, Greece, Canada)

International audienc