Wide, healthy and safe sandy beaches are of major interest from the perspective of recreational and economic activity. In addition, sandy beaches are a strategic location for navy activities (unloading of troops, equipment or supplies; infrastructure protection; land mine detection). Yet, among all the different types of coasts (sandy, muddy and rocky), wave-dominated sandy beaches are the most unpredictable, dynamic and poorly understood coastal systems. Our project aims at improving our understanding of sandy coast behaviour. The numerical modelling and data collection approach proposed in the frame of CHIPO relies on an in-depth literature review, over the last 15 years, of scientific advances in sandy beach morphodynamics and long-term coastal evolution in which the contribution of our research group is internationally acknowledged. A fundamental step that we identified is that combining cross-shore and longshore processes will drastically improve our understanding and ability to predict three-dimensional sandy beach morphodynamics and long-term shoreline variability. Until now, cross-shore and longshore processes have been addressed in isolation worldwide. This combination, which is arguably a necessary requirement to understand and predict coastal evolution, is the common thread of CHIPO. Our project relies on the development of two numerical models, which will be unique in the international scientific community, and long-term shoreline data. The main field site is the Aquitaine coast but, in the framework of international collaborations, we will also use long-term shoreline data from seven international beaches spanning a wide range of environmental variables (wave climate, sediment grain size, geological constraints). Combining innovative numerical modelling and this dataset, the primary objectives of CHIPO are (1) to identify the respective contributions of cross-shore and longshore processes to both sandy beach morphodynamics and long-term shoreline evolution, (2) to develop two state-of-the-art efficient numerical tools and (3) improve our understanding and ability to simulate and further predict coastal evolution on timescales ranging from a few hours to decades. CHIPO is innovative because it paves a gap in the French scientific community as no research group currently addresses the numerical modelling of long-term coastal evolution. In addition, French research groups essentially rely on complex process-based modelling. Here, in the frame of long-term modelling, behaviour-oriented and cellular automaton will be developed which will allow us to (1) perform long-term simulations with reasonable computation cost and (2) avoid the effects of the misspecifications of the physics that inevitably cascade up through the scales in complex process-based nonlinear models and result in unreliable simulations on long timescales. Our project, which builds on an in-depth literature review and the clear identification of scientific problems, is both efficient and inexpensive, and relies the internationally-acknowledged expertise of a group of productive young researchers (according to ANR’s definition). CHIPO will lead to strong scientific advances and outreach activities (dissemination, public engagement, knowledge exchange) and engagement with the public and private stakeholders will be a priority of CHIPO. The numerical models developed within the framework of CHIPO will be made available for the ECORS demonstrator.

Coastal zones are essential for social and economical developments. Located at the interface between ocean and continent, the coasts are vulnerable to environmental hazard and are currently facing an intensification of risk associated with increasing human pressure and the context of global climate change. This project focuses on two regions of the world particularly exposed to coastal vulnerability: West Africa and Vietnam. The environmental conditions governing hydro-sedimentary functioning differ drastically between the two regions. Erosion in West Africa is induced all year long by high-energy long swells; in contrast, Vietnam shows paroxystic events induced by typhoons. Even though the societal issues are manifest in these areas, their hydro-sedimentary functioning remains poorly known and limits social and economical development. The objective of the COASTVAR project is to advance our understanding by characterizing the morphological evolution (aerial and submerged), the driving forces and hydro-morphodynamic processes, from event to seasonal and interannual scales. Emphasis will be given to extreme events and their long-term effect, and to surf-shelf exchanges associated with the wave-induced circulation. In the first project task, innovative observational tools (video imagery and drone) will be used in addition to conventional instruments. In a second task, deep-water wave conditions will be downscaled to the beach, then nearshore configurations of a 3D coupled wave-current model will be set up. In a third task, the ECORS beach evolution predictor (PEA SHOM-DGA), which was yet only tested in mid-latitude environments, will be applied for the first time to tropical coastal systems. Our objective here is to obtain a generic operational tool that can be applied to any coast in the world. The research developed in the COASTVAR project has a strong dual aspect. First, it will provide the first high quality survey and forecasting system for the selected regions (waves, currents and bathymetry), which will be highly relevant to military action. Then, it will propose tools to anticipate coastal risks (erosion and submersion), quantify vulnerability and exposure of people to hazard, and lay solid grounds to improve coastal management.

Bioaccumulation of mercury from the bottom to the top of the food chain is a worldwide concern for ecosystem health and human food supply. Associations of Hg with natural organic matter (NOM), especially with reduced sulfur, to a great extent determine the bioavailability and toxicity of this hazardous element in the biosphere. There is, however, a huge unmet need for improved understanding of (1) how Hg is bound at the molecular-scale in NOM, (2) how its bonding environment influences its solubility, hence its mobility and subsequent uptake into the food chain, and (3) how it is bioaccumulated and detoxified in biological tissues such as fish (e.g., brain, liver, kidney, muscles) and hairs of human beings (medulla, cortex and cuticule). These fundamental questions are crucial to mitigate the impact of Hg on the biosphere. In this proposal, experiments relevant to natural processes and direct measurements on Hg-affected animals and humans are designed to examine (1) relationships between the speciation of Hg in dissolved organic matter (DOM) and its bioaccumulation and detoxification in the tissues of fish, taking Danio rerio (zebrafish) as the model animal in the laboratory, (2) the compartmentation of Hg among tissues down to cell organelles in D. rerio, in insectivorous fishes and fish eaters from French Guiana, and among the three major identifiable tissular regions of the hairs of contaminated Wayana and Wayampis Amerindians, and (3) the sequestration forms of Hg in all these tissues. The research is driven by six hypotheses, which will be tested by an interdisciplinary and international team of researchers : a) Hg is dominantly speciated as HgxSy clusters in DOM at concentrations relevant to realistic environmental processes, and their amounts depend on the concentration of cysteine-like thiolated sulphur groups. b) DOM-associated Hg modulates mercury and methylmercury transfer in the water column and in fine the overall bioavailability of this element. c) The detoxification form(s) of Hg differ, to an extent to be determined, (1) among organisms and tissues, in particular between the brain, liver, and muscles of fish; selenium may precipitate mercury in some tissues, as observed in mammals, and (2) through the food web from vegetarian/insectivorous to predatory fishes to humans. d) Hg-thiolate clusters in metalloproteins produced by cells to detoxify Hg are analogous to the HgxSy clusters in DOM. e) The expression of the mt1 and mt2 genes, which encode the two metallothionein isoforms MT-I and MT-II in D. rerio, is influenced by the speciation of Hg. f) The nature of the HgxSy clusters in DOM influences mercury ecotoxicity and modulates such outcomes as adaptive genetic response, mitochondrial impairment, swimming behaviour, and genotoxicity in zebrafish, and genotoxicity in S. subspicatus. Beyond the discovery of fundamental processes that control the bioavailability and toxicity of this global environmental contaminant and the mere production of high-quality scientific articles of wide interest to a large community of scientists and to media, the broader societal benefit of this proposal is to dissociate, for the first time, speciation and concentration in the evaluation of the bioaccumulation and toxicity of Hg. This knowledge is essential to improve the reliability and significance of assays for assessing mercury toxicity by taking into account the real form of Hg in the environment. So far, acute toxicity tests are performed with free ionic or small molecular Hg species, which are not relevant to natural conditions.

The salinity and heat balance of the North Atlantic region is of paramount importance for the Northern Hemisphere climate and is intimately tied to the northward transport of heat and salt through the gyre and intergyre circulations and the Atlantic Meridional Overturning Circulation (AMOC), as revealed by modern hydrographical observations and model simulations. However, little is known about the long-term and low frequency (centennial to millennial) Atlantic gyres variability and their link to climate as well as to salt and heat contributions from the Mediterranean Sea. Previous studies have shown that sub-millennial variability throughout the last 11,500 years (the Holocene) are modulated by wind forcing and freshwater fluxes affecting the subpolar gyre strength and thus the surface properties of the North Atlantic waters entering the Nordic Seas. During the Holocene, the North Atlantic/European climate, including the Mediterranean area, have undergone significant changes as recorded by sea surface temperatures (SSTs), continental precipitation and air temperature reconstructions. Understanding the causes of climate variability in proxy records requires an integrated approach combining surface and sub-surface ocean properties and continental time series at decadal to centennial time-scales and their comparison with model simulations. This project aims at producing robust geochemical proxy reconstructions in key regions of the North Atlantic and Mediterranean Sea for the past 11,500 years by using paleoceanographic proxies of SST (d18O and Mg/Ca from foraminifera, alkenones, derived quantification from microfossil assemblages), geochemical water mass tracers (eNd and d13C of foraminiferal tests) as well as novel tracers (eNd, Li/Mg) recorded in precisely dated cold-water corals (U/Th dating). Paleoclimate reconstructions will be evaluated against instrumental data over the 20th century, when possible, using modern corals and sediments collected with box-corers and ROV. To reach these objectives, our strategy will take advantage of the successful developments and scientific partnership of the ANR PICC, IDEGLACE (2005-2009) and NEWTON (2006-2010) previous projects. The HAMOC project will also benefit from the unique sample collections gathered during the past ten years of research on cold-water coral collection from along the eastern European margin and Mediterranean basin (INSU ICE-CTD, projects FP6 HERMES, FP7 HERMIONE, FP7 EPOCA, and FP7 CORALFISH) and interactions with European climate projects such as the FP7 Past4Future that produced numerical simulations and climate reconstructions including the Holocene period. Finally, HAMOC will strongly benefit from new laboratory infrastructure such as cutting edge mass spectrometry techniques (Neptuneplus MC-ICPMS – IDES/LSCE and CEREGE) and recent analytical developments for rapid and precise isotope measurements (eNd) and age determination (U-series and AMS 14C dating) on corals. On the modelling side, the project will benefit from long simulations over the Holocene from the state-of-the-art IPSLCM5A climate model where ocean tracers are implemented. Broader Impacts: The project will document the relationships between climate and cold-water coral ecosystems in the North Atlantic and Mediterranean Sea. This project will further support the career of young research fellows (PhD students and postdocs) who will develop their scientific skills in an emerging field linking marine geochemistry, oceanography and climatology expertises. The consortium will dedicate a significant effort for public outreach to raise awareness on coral ecosystems and the natural climate variability of the North Atlantic Ocean.

Understanding the chemistry (sources, fate, processing) of tropospheric aerosols and radicals is key for our ability to understand our changing planet. However, a number of indicators are showing that our knowledge is far to be complete. Just over the last years, important findings were made associated either with some unexpected cycling of HOx radicals or with the importance of Criegee Biradicals (CBs) produced during the ozonolysis of unsaturated volatile organic compounds. The CBs may either promptly decompose leading to formation of radicals (OH, RO2) or be collisionaly stabilised and undergo reactions with NOx, SO2, H2O as well as with other organic compounds. The reaction of certain CBs with SO2 leading to the H2SO4 formation has been found very recently to be surprisingly fast and questioning the role of the Criegee biradicals in sulfuric acid formation. Such findings have initiated very intense discussion in the scientific community as they have the potential to drastically affect our understanding of the tropospheric self-cleansing properties. It appears clear that atmospheric chemistry is currently evolving at a very high pace highlighting or discovering new scientific challenges of the highest importance! The combination of an increased self-cleansing capacity with new pathways leading to new particle formation and growth is obviously a major challenge that needs to be resolved to increase our capacity to understand and simulate our changing atmosphere! The COGNAC project therefore suggest tackling this issue by performing laboratory based experiments to derive scientifically sound data on the chemistry of CBs and NO3 (both homogeneously in the gas phase and heterogeneously involving SOA ozonolysis); by providing new kinetic and mechanistic data describing the formation at the gas-particle interface of organo-sulfates to assess the potential importance of these in providing organic particulate matter and finally by incorporating the laboratory derived mechanism and process in the box and chemical transport models to improve the performance of these models in predicting atmospheric oxidative capacity and aerosol distribution. COGNAC is a highly innovative project addressing one of the most pressing challenges in tropospheric chemistry.