The functioning and productivity of oligotrophic systems, and the balance between production and mineralization in these oceanic areas, is still the subject of much debate. Once thought to be biological deserts, recent research has shown that these systems could largely contribute to the global ocean organic carbon (C) export. It is important to thoroughly understand the biogeochemical functioning of these vast ecosystems in order to characterize their evolution in the context of climate alteration. This project aims to give a zonal characterization of the biogeochemical functioning and biological diversity of the South West (SW) Pacific toward a gradient of macro- and micro-nutrients availability, and produces a detailed study of the biological production and its subsequent fate in 3 contrasting sites, with a specific emphasis on the production sustained by dinitrogen (N2) fixation. We will determine whether organic matter production, re-mineralization and export processes are different at these sites, and if so, determine how these differences are related with the diversity/functioning of N2-fixing organisms in the planktonic community. Comparing different sites, along a zonal gradient of variable nutrient availability, should provide us with a new insight for identifying and understanding the fundamental interactions between marine biogeochemistry and ecosystems. We will focus on several current issues of interest regarding the coupling/uncoupling between carbon and nutrient (N,P,Si,Fe) delivery and removal processes in the surface layer. These processes control the planktonic community structure and functioning and, ultimately, the ability of the ocean to biologically sequester C. We shall describe the functioning of each distinct ecosystem under physical conditions with new approaches combining satellite localization and drifters for Lagrangian strategy, and, finally, examine the biogeochemical role of diazotrophs in each system, using experimental and modelling approaches. The scientific objectives will be achieved through the realization of 6 complementary Tasks (including promotion of Science, Task 6) involving international collaborations between physicists, biologists and biogeochemists with expertises ranging from marine physics, chemistry, optics, biogeochemistry, microbiology, molecular ecology, genetics, and modelling. The overall strategy of the project will combine experimental and modelling approaches. The experimental part is based on the realization of a 45-days oceanographic cruise onboard the R/V L’Atalante in the SW Pacific in 2015. The cruise will consist in 18 short duration (8 h) stations (SD stations) and 3 long duration (7 d) stations (LD stations) distributed along a zonal transect (19° S) in the SW Pacific ocean. During the SD stations, a characterization of the biogeochemistry and biological diversity from the North of New Caledonia to the western border of the South Pacific gyre will be performed (Task 1). The LD stations will allow to perform a process studies in contrasting oligotrophic and N2 fixation conditions following a Lagrangian approach for a 3D characterization of the upper water column (Task 2). During the LD stations, high frequency acquisition of physical, optical, biogeochemical and biological variables will be assessed. We will quantify primary / secondary production and their fate (Task 3), as well as mineralization and export of organic matter (Task 4) by measuring biogenic element (C,N,P,Si) stocks/fluxes and organisms responsibles for these fluxes (“Who does what?”). Moreover, a multi-scale modelling approach is proposed that we plan to start from the beginning of the OUTPACE project (Task 5). Its objective is to complement the observations with the analyzed data in order to better understand the interactions between the biogeochemical cycles of the biogenic elements (predominantly the C cycle) and the dynamics of the planktonic trophic network in oligotrophic marine areas.

ROADMAP investigates the influence of North Atlantic and North Pacific ocean surface variability on the extratropical atmospheric circulation, with a focus on high-impact weather and climate extremes under present-day and future climate conditions. Specifically, ROADMAP will address: • impacts of a changing ocean circulation on sea surface temperature (SST) • future of western boundary currents and their extensions, such as the Gulfstream • extratropical ocean-atmosphere interactions controlling jet streams, cyclones, blocking and their links to weather and climate extremes • impacts of tropical SST anomalies (e.g. El Nino) on the extratropical atmospheric circulation • role of the SST and Arctic sea ice for driving impact-relevant atmospheric extremes such as heat waves including compound weather extremes • intensity and frequency of Mediterranean mesoscale cyclones (Medicanes) • interactions between oceanic and atmospheric modes of variability ROADMAP will exploit the wealth of model simulations recently produced in other international (EU and worldwide) research activities. Additionally, ROADMAP will conduct dedicated experiments employing cutting-edge numerical techniques based on data assimilation and interactive ensemble modelling. Analyses will be based on advanced dynamical and statistical methods as well as novel machine learning techniques designed to infer complex, non-linear relationships. ROADMAP applies a multi-model approach, crucial for assessing uncertainties. Results will be disseminated to the scientific, stakeholder and climate service community as well the general public. The consortium encompasses leading climate research institutions from seven European countries, including universities as well as institutions providing (national) meteorological and climate services. ROADMAP will continue a long-standing history of successful international collaboration between its partners.

Ocean Acidification (OA) owing to increasing atmospheric CO2 may have profound impacts on marine ecosystems including coral reefs that may lose their fundamental function of reef construction. However, large spatial-temporal variation and technological hurdles of monitoring seawater carbonate chemistry prohibit accurate predictions of OA impacts on coral reefs, and thus, effective mitigation and adaptation strategies. Here, we propose to first establish an innovative methodology for monitoring of OA, replicable across the world. The authors of this proposal are the inventors of the core technology. As a second step, we propose to monitor and model seawater carbonate chemistry (pH-alkalinity) and reef calcification capacity in five sites (Okinawa, Hawaii, Réunion, Mayotte Islands, and Tonga). Other good practices in OA management will be evaluated for cross-learning between the five sites. One example we are aiming to evaluate is seaweed farming to absorb CO2 and promote coral growth. Fisheries in Onna-son village in Okinawa, Japan have been culturing corals and seaweed simultaneously for decades with empirical knowledge that they stimulate mutual growth, but with no knowledge of the underlying mechanism. By providing scientific evidence, this "Onna-son model" may be of potential interest in other sites. The final objective of this consortium is to construct a "toolbox" consisting of tools such as methodology and good practices in science, technology, socio-economic models, climate change adaptation/mitigation, and policy aimed at ameliorating negative impacts of OA in coral reefs. We aim to maintain close communication with local and national stakeholders as well as international organizations throughout the project. We will conduct outreach, education and training efforts at both local and international events. Data management will be conducted in line with the Belmont Forum Open Data Policy and Principles. Special attention will be paid to the gender dimensions of the project.

The ANR MEDSALT project aims to consolidate and expand a scientific network recently formed with the purpose to use scientific drilling to address the causes, timing, emplacement mechanisms and consequences of the largest and most recent 'salt giant' on Earth: the late Miocene (Messinian) salt deposit in the Mediterranean basin. After obtaining the endorsement of the International Ocean Discovery Program (IODP) on a Multiplatform Drilling Proposal (umbrella proposal) in early 2015, the network is planning to submit a site-specific drilling proposal to drill a transect of holes with the R/V Joides Resolution in the evaporite-bearing southern margin of the Balearic promontory in the Western Mediterranean - the aim is to submit the full proposal before the IODP dealine of April 1st 2017, following the submission of a pre-proposal on October 1st 2015. Four key issues will be addressed: 1) What are the causes, timing and emplacement mechanisms of the Mediterranean salt giant ? 2) What are the factors responsible for early salt deformation and fluid flow across and out of the halite layer ? 3) Do salt giants promote the development of a phylogenetically diverse and exceptionally active deep biosphere ? 4) What are the mechanisms underlying the spectacular vertical motions inside basins and their margins ? Our nascent scientific network will consit of a core group of 22 scientists from 10 countries (7 European + USA + Japan + Israel) of which three french scientists (G. Aloisi, J. Lofi and M. Rabineau) play a leading role as PIs of Mediterranean drilling proposals developed within our initiative. Support to this core group will be provided by a supplementary group of 21 scientists that will provide critical knowledge in key areas of our project. The ANR MEDSALT network will finance key actions that include: organising a 43 participants workshops to strengthen and consolidate the Mediterranean drilling community, supporting the participation of network scientists to seismic well site-survey cruises, organising meetings in smaller groups to work on site survey data and finance trips to the US to defend our drilling proposal in front of the IODP Environmental Protection and Safety Panel (EPSP). The MEDSALT drilling initiative will impact the understanding of issues as diverse as submarine geohazards, sub-salt hydrocarbon reservoirs and life in the deep subsurface. This is a unique opportunity for the French scientific community to play a leading role, next to our international partners, in tackling one of the most intellectually challenging open problems in the history of our planet.

This project, which builds on the results of the ANR COCOA project, aims at improving the representation of turbulent ocean-atmosphere exchanges in climate models by taking into account their modulation by waves using ocean-waves-atmosphere coupled modelling systems. Waves form by absorbing momentum in areas of storms and tropical cyclones, and transmit part of it to the ocean, with an impact on deep mixing and the overall heat balance. This energy absorbed by waves can be transported by swell over very long distances, from energetic areas (Southern Ocean, storms) to the inter-tropical band, for example. In this inter-tropical zone, where much of the heat and moisture exchange that drives atmospheric circulation on climatic scales takes place, conditions are met for swell to impact air-sea fluxes. It is therefore important to take into account the impact of waves in energetic zones, where they are formed and a large part of the energy is transferred to the ocean, and in dissipation zones, where they have an impact on surface fluxes. We plan to: 1) quantify the impact of wave-related processes on atmosphere-wave and wave-ocean exchanges at climate scales, based on existing model representations; 2) develop and validate new parameterizations to take into account, in coupled ocean-wave-atmosphere models at climate scales, processes related to tropical cyclones, the effect of waves on ocean mixing, and swell; 3) to build a coupled system around the wave model, ensuring complete consistency of momentum exchanges by resolving the inconsistencies of most of the current coupled systems used at weather prediction scales. This project should pave the way for state-of-the-art consideration of wave effects in climate models.