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    In the framework of the SNO/SOERE MOOSE (Mediterranean Ocean Observing System on Environment https://www.ir-ilico.fr/Les-reseaux-elementaires/Fiches-d-identite-des-reseaux-elementaires/MOOSE ) program, the Mediterranean Institute of Oceanography is operating coastal High Frequency Surface Wave Radars (HF radar) on the North Western Mediterranean coast. This activity is also supported by the following European Research Infrastructure Jerico-Next (https://www.jerico-ri.eu), and Intereg MED programs as Impact and Sicomar +. HF radar provide high resolution (3­-5 km), synoptic view of surface currents from the shore up to 80 km off shore at hourly time scales. The measurement principle is based on the Doppler effect created by an additional current on the intrinsic speed of the waves selected by radar-sea interactions, called Bragg waves, having a wavelength of half that of the radar e.m. waves and propagating in the axis of observation (radial currents). A single radar scans the sea in azimuth and determines the radial components of the current at each adjacent cell along each azimuth. Two separate radars for the same area from different angles then collect the information necessary for mapping vector current from the combination of the two sets of radial components. The HF radar data set is made of monthly averaged surface currents, geo-referenced on cartesian lon/lat coordinates. The radial velocities maps are provided applying a Direction Finding technique (instead of traditional Beam Forming) not only to the full array of antenna but also to subarrays made of a smaller number of sequential antennas, a method which we refer to as "antenna grouping". Radials from Peyras-Peyras and Porquerolles-Benat are computed to reconstruct the vector field.

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    "Towards an integrated prediction of Land & Sea Responses to global change in the Mediterranean Basin" The LaSeR-Med project aims at investigating the effects of climate change and of mediterranean population growth on some major indicators of the Mediterranean Sea (primary production, carbon export, zooplankton biomass available for small pelagic fishes, pH, dissolved oxygen) using and integrated model encompassing a socio-economic model, a continental model of agro-ecosystems, and a physical ocean-atmosphere model coupled to a biogeochemical model of the ocean. Last, a model for the widespread species of jellyfish Pelagia Noctiluca (Berline et al., 2013) uses biogeochemical outputs as food forcing for the jellyfish. In this project, our first aim was to investigate the large-scale and long-term impacts of variations in river inputs on the biogeochemistry of the Mediterranean Sea over the last decades (see Pages et al., 2020a). This interdisciplinary project provided the framework for joint discussions on each of the sub-models that constitute the integrated model, namely the socio-economic model (Ami et al., in prep., Mardesic et al., in prep.) created ex nihilo by researchers from AMSE, INRA and GREQAM, the continental agro-ecosystem model LPJmL (Bondeau et al., 2007) worked on at IMBE so as to include the nitrogen and phosphorous cycles in the frame of the present project, and the ocean biogeochemical model Eco3M-Med developed at MIO (Baklouti et al., 2006; Alekseenko et al. 2014, Guyennon et al., 2015; Pagès et al., 2020a), forced by ocean physics, either using the ocean model NEMO-Med12 forced by atmosphere at IPSL (simulation NM12-FREE run with the NEMO-MED12 model and used for our hindcast simulation, see below) or a coupled ocean-atmosphere model at CNRM (physical forcing provided by CNRM-RCSM4, see below). Details on simulation NM12-free: The historical simulation used in this work is referred to as the NM12-FREE (no reanalysis no data assimilation) which started in October 1979 and ended in June 2013 (Hamon et al., 2016). It has been run with the general circulation model NEMO in its regional configuration NEMO-MED12 based on a horizontal resolution of 1/12 de degree (6.5 to 8 km cells) and a 75-level vertical resolution (of 1 m width at the surface to 135 m at the seabed). For this simulation, runoff and river inputs in the NM12 domain came from the inter-annual data of Ludwig et al. (2009) and the atmospheric forcing was based on the dynamical downscaling of the ERA-INTERIM reanalysis, i.e. ALDERA which has a 12 km spatial resolution and a 3 h temporal resolution. More details on the NM12-FREE simulation are given in Hamon et al. (2016). Keywords: - Mediterranean Sea, river inputs, chlorophyll, nutrients, phytoplankton, bacteria, zooplankton, dissolved and particulate organic detrital matter Citation: Pagès, R., Baklouti, M., Barrier, N., Richon, C., Dutay, J.-C., and Moutin, T. (2020a). Changes in rivers inputs during the last decades significantly impacted the biogeochemistry of the eastern Mediterranean basin: a modelling study. Prog. Oceanogr. 181:102242. doi:10.1016/j.pocean.2019.102242 Ayache, M., Bondeau, A., Pagès, R., Barrier, N., Ostberg, S. and Baklouti, M. (2020). LPJmL-Med – Modelling the dynamics of the land-sea nutrient transfer over the Mediterranean region–version 1: Model description and evaluation. Geoscientific Model Development Discussions, Copernicus Publ.

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    "Towards an integrated prediction of Land & Sea Responses to global change in the Mediterranean Basin" The LaSeR-Med project aims at investigating the effects of climate change and of mediterranean population growth on some major indicators of the Mediterranean Sea (primary production, carbon export, zooplankton biomass available for small pelagic fishes, pH, dissolved oxygen) using and integrated model encompassing a socio-economic model, a continental model of agro-ecosystems, and a physical ocean-atmosphere model coupled to a biogeochemical model of the ocean. Last, a model for the widespread species of jellyfish Pelagia Noctiluca (Berline et al., 2013) uses biogeochemical outputs as food forcing for the jellyfish. In this project, our aim was first to investigate the large-scale and long-term impacts of variations in river inputs on the biogeochemistry of the Mediterranean Sea over the last decades (see Pages et al., 2020a). In the second phase, a climate scenario (RCP8.5) alone (Pages et al., 2020b) or combined with a “land-use” scenario derived to ensure the same level of food availability as today in 2050 have been run to investigate its effect on these indicators and to analyze the observed changes on the structure and the functioning of planktonic food web. This interdisciplinary project provided the framework for joint discussions on each of the sub-models that constitute the integrated model, namely the socio-economic model (Ami et al., in prep., Mardesic et al., in prep.) created ex nihilo by researchers from AMSE, INRA and GREQAM, the continental agro-ecosystem model LPJmL (Bondeau et al., 2007) worked on at IMBE so as to include the nitrogen and phosphorous cycles in the frame of the present project, and the ocean biogeochemical model Eco3M-Med developed at MIO (Baklouti et al., 2006; Alekseenko et al. 2014, Guyennon et al., 2015; Pagès et al., 2020a), forced by ocean physics, either using the ocean model NEMO-Med12 forced by atmosphere at IPSL (simulation NM12-FREE run with the NEMO-MED12 model and used for our hindcast simulation, see below) or a coupled ocean-atmosphere model at CNRM (physical forcing provided by CNRM-RCSM4, see below). Details on the CNRM-RCSM4 model The CNRM-RCSM4 simulates the main components of the Mediterranean regional climate system and their interactions. It includes four different components: (i) The atmospheric regional model ALADIN-Climate (Radu et al., 2008; Colin et al., 2010; Herrmann et al., 2011) characterized by a 50 km horizontal resolution, 31 vertical levels, and a time step of 1800 s, (ii) the ISBA (Interaction between Soil Biosphere and Atmosphere) land-surface model (Noilhan and Mahfouf, 1996) at a 50 km horizontal resolution, (iii) the TRIP (Total Runoff Integrating Pathways) river routing model (Oki and Sud, 1998), used to convert the runoff simulated by ISBA into rivers (Decharme et al., 2010; Szczypta et al., 2012; Voldoire et al., 2013), and (iv) the Ocean general circulation model NEMO (Nucleus for European Modeling of the Ocean, Madec and NEMO-Team, 2016) in its NEMO-MED8 regional configuration (Beuvier et al., 2010). NEMO-MED8 is characterized by a horizontal resolution of 1/8° (grid cells size from 6 to 12 km), a vertical resolution of 43 vertical levels (cell height ranging from 6 to 200 m), and a time step of 1200 s. More details about the CNRM-RCSM4 model can be found in Sevault et al. (2014). Keywords: - Mediterranean Sea, river inputs, chlorophyll, nutrients, phytoplankton, bacteria, zooplankton, dissolved and particulate organic detrital matter Citation: Pagès, R., Baklouti, M., Barrier, N., Richon, C., Dutay, J.-C., and Moutin, T. (2020a). Changes in rivers inputs during the last decades significantly impacted the biogeochemistry of the eastern Mediterranean basin: a modelling study. Prog. Oceanogr. 181:102242. doi:10.1016/j.pocean.2019.102242 Pagès, R., Baklouti, M., Barrier, N., Ayache, M., Sevault, F., Somot, S. and Moutin, T. (2020b). Projected Effects of Climate-Induced Changes in Hydrodynamics on the Biogeochemistry of the Mediterranean Sea Under the RCP 8.5 Regional Climate Scenario. Front. Mar. Sci. 7:563615. doi:10.3389/fmars.2020.563615 Ayache, M., Bondeau, A., Pagès, R., Barrier, N., Ostberg, S. and Baklouti, M. (2020). LPJmL-Med – Modelling the dynamics of the land-sea nutrient transfer over the Mediterranean region–version 1: Model description and evaluation. Geoscientific Model Development Discussions, Copernicus Publ.

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    The FUMSECK (Facilities for Updating the Mediterranean Submesoscale - Ecosystem Coupling Knowledge) cruise aimed at performing technological tests of several instruments exploited for the study of the (sub)meso-scale processes and dynamics (from 0.1 to 100 km for a lifetime from several days to several weeks). Three categories of tests have been performed. The first category is the study of the MVP (Moving Vessel Profiler) tracked instruments behaviour, in particular the MSFFFII (Multi Sensor Free Fall Fish, so called "big fish"). We focused on the rotative behaviour of the big fish during its falling and raising, the connectics between the instrument and the MVP cable, between the platform and the boat depth sensor, and between the platform and the PC used to analyse the data, hence testing the whole data acquisition chain. The second category concerns the exploration of several methods to access the measurement of the current velocities vertical component, using different ADCP (Hull-mounted ADCP, Fixed-depth and profiling L-ADCP and Sentinel V (5 beams), Free-Fall ADCP), a prototype of a vertical velocity profiler, and a glider. Finally, we experimented the release of a sample of biodegradable coloured micro-particles at 15m-depth and within a 1 hectare surface, their tracking with drifting buoys, their extraction by pumping and their detection by cytometry. The goal of this experiment was its feasibility, in order to use these micro-particules as tracers for the understanding of the physical part of the ocean biological Carbon pump. Data acquired during the campain are : - Biological oceanography : * B08 Phytoplankton 7 days Continuous sampling for cytometer analysis. 15m-depth sampling for cytometer analysis (3 samples). 30.04.2019 * B90 Other biological/fisheries meas. 1 days GoPro images for the injection, the following and the sampling of coloured micro-particles. 30.04.2019 - Physical oceanography : * D05 Surface drifters/drifting buoys 3 deployments Injection, following, and sampling of coloured micro-particles at 15m-depth. Deployment and recovery of lagrangian drifters anchored at 15m for water mass following. 30.04.2019 * D71 Current profiler (eg ADCP) 7 days Continuous Vessel-Mounted ADCP. L-ADCP and Sentinel casts (5 and 6 stations). Free-Fall ADCP (6 stations). 30.04.2019 * D90 Other physical oceanographic meas. 7 days MVP (Moving Vessel Profiler) 30.04.2019 * D90 Other physical oceanographic meas. 6 stations VVP (Vertical Velocity Profiler) 30.04.2019 * H10 CTD stations 6 stations CTD casts 30.04.2019 * H71 Surface measurements underway (T,S) 7 days Continuous measurement 30.04.2019

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    The scientific objectives of the project MAUPITI HOE are to understand the hydrodynamics of an archetypal reef-lagoon system of a high volcanic reef island. The physical functioning of the hydrosystem involves a fine coupling between water levels, waves (including wind, infragravity and VLF waves), currents and seabed structure (reef roughness). The present data focuses on the reef barrier dynamics. Citation: - Sous D., Bouchette F., Certain R., Meulé S. (2021). Maupiti Hoe 2018 [Data set]. MIO UMR 7294 CNRS, GLADYS. https://doi.org/10.34930/9DB3BEC4-0BBF-4531-8864-F100C4B8ECED

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    Daily High Frequency Radar (HFR) surface current data (radial velocity files and total velocity file) from 2 different stations located on the French Mediterranean coast (Toulon), spanning from January 2012 to December 2019. The radial datasets have been processed to remove outliers. Then, the gaps in the data have been filled using the DINEOF algorithm. The total velocity is then reconstructed from the filled radial velocity files, and projected onto a cartesian grid of 1km x 1km. The HFR data comes from two systems, one monostatic radar PEY (located at Fort Peyras, La Seyne sur mer), and one bistatic POB (emitter located at Cap Bénat - Bormes les Mimosas, and transmitter on Porquerolles Island). The HFR data is initially hourly sampled. To remove the outliers of the data, for each timestep, a Probability Density Function (PDF) is computed on the spatial gradient of each radial map. Pixels with a spatial gradient with a probability under 3% are removed. Additionnally, for each pixel, a PDF is computed on the temporal gradient of its whole timeseries. Timesteps with a temporal gradient that have a probability under 1% are then removed. Then we proceed to a preliminary temporal and spatial hole filling of the missing data. For the timeseries of each pixel, timesteps that are surrounded by valid values within 3 hours (i.e. 3 timesteps) are filled by a weighted linear interpolation. For each timestep, pixels of the map surrounded by values within 1 grid point are filled in the same way. The radial data is then daily averaged. The DINEOF algorithm (http://modb.oce.ulg.ac.be/mediawiki/index.php/DINEOF) is run in a multivariate way (2 radial velocity files) using 50 EOF modes for the reconstruction. At some timesteps (shown by the flag variable of the file), the filling has not been possible, and the missing maps have been replaced by the temporal average radial map. The filled radial velocities are then locally interpolated onto a cartesian grid of 1km spatial resolution using a Weighted Least Square method. HF radar sites : - Peyras : 43°03'47.4"N, 5°51'40.3"E - Porquerolles (transmitter only): 42°58'59.0"N, 6°12'15.3"E - Bénat (receiver only): 43°05'31.5"N, 6°21'26.5"E EUROPEAN DIRECTORY OF MARINE ENVIRONMENTAL RESEARCH PROJECTS (EDMERP) : - SICOMAR PLUS(12402), IMPACT(12271), MOOSE(11574), and JERICO NEXT(12227) EQUIPEMENTS: - High Frequency Surface Wave radar WERA from HELZEL MESSTECHNIK PARAMETERS: - sea surface current Citation: Molcard, A., & Bourg, N. (2021). HF RADAR - French Riviera (Mediterranean Institute of Oceanography) - daily surface currents filled with DINEOF [Data set]. MIO UMR 7294 CNRS. https://doi.org/10.34930/9263C4DF-4F55-4C5A-B183-C40EE1D844B1

  • Wind is generated from left to right by an imposed constant horizontal pressure gradient. The initial wind field is disturbed by small random variations so as to produce a turbulent field. Withouth the perturbations, a viscous solution would be found. The numerical resolution technique used is based on finite differences, applied to a structured mesh. The Continuity and Navier-Stokes equations are solved with the well-known half time-step method, in which the Poisson equation is solved over the entire domain at each time iteration. As of 17 March 2022, the code version is DNS_2D_for_Teaching-v1.0.0. The code is written in C language. A GUI (Graphical User Interface) is available as an executable file "sdiapp.exe" that can be run under most versions of Microsoft Windows. Please just make sure to check the 'graph' box before clicking on the launch button, to have the visual experience. On the GUI, two graphs give an overview of the real time simulation. The top graph shows the 2D (x,z) vorticity, while the bottom graph shows the wind speed. The colour bars are not shown, but they are classical tables in which blue means small values, while red colours denote large values. The authors of this code version are Francis Vivat (LATMOS UMR CNRS 8190) and Denis Bourras (MIO UMR 7294). The code is distributed freely and comes with no garantees. It was mainly designed for educational purposes. Please note that the rules of use must follow the CeCILL-C FREE SOFTWARE LICENSE AGREEMENT included in the distribution. Any return is welcomed and encouraged, please contact francis.vivat@latmos.ipsl.fr or denis.bourras@mio.osupytheas.fr. Citation: Vivat, F., & Bourras, D., (2023). DNS_2D_for_Education [Application].

  • This Application is a simple calculator that estimates Turbulent Air-Sea Fluxes based on input variables such as wind speed, air temperature, or relative humidity. The input variables can be easily set by hand with sliders. The present Air-Sea Flux Calculator application makes it easy to get an estimate of the fluxes at Sea of for Educational purposes The code is a simplification of the well known bulk algorithm so-called COARE 3.0 (Fairall et al. 2003). The authors of this code are Nicolas Bourras and Denis Bourras (MIO CNRS UMR 7294, Institut Méditerranéen d'Océanologie, Institut Pytheas CNRS UAR 3470, Aix-Marseille University). Citation: Bourras, N., & Bourras, D., (2023). Air-Sea flux calculator [Application].

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    Maupiti ("the Stuck Twins'') is a diamond-shaped island located in the western part of the Society archipelago in French Polynesia. The present study focuses on the data recovered over a single cross-barrier transect located in the south-west barrier during the MAUPITI HOE field campaign, from 5 to 18 July 2018. The studied area is representative of the reef structure observed along the 4km-long southwestern barrier reef, showing an alongshore-uniform structure exposed to swell approaching with weak incident angles, a healthy reef colony. In the cross-barrier direction, the reef displays a clear partitioning of bottom roughness that ranges from low-crested compact structures at the reef crest to higher and sparser coral bommies on the backreef. The experimental setup was specifically designed to analyse and differentiate the dynamics over three roughness-contrasting sections found over the barrier reef. Four pressure sensors (OSS3, OSS4, OSS5, OSS6) have been deployed across the reef flat/ backreef, outside the surf zone. The bottom pressure is measured continuously at 10 Hz, and are converted into free surface elevation assuming hydrostaticity. An electrocurrent meter S4 provides the wave forcing while AQP1 is a velocity profiler providing the transports. The bed profile is obtained from the combination of (I) boat survey in the deeper part and (ii) high resolution GNSS RTK topography by feet. S4 position : -16.47109°N; -152.2782°E OSS3 position: -16.46968°N; -152.27698°E OSS4 position : -16.46931°N; -152.27676°E OSS5 position : -16.46851°N;-152.27614°E OSS6 position: -16.46706°N; -152.27504°E AQP1 position: -16.46318°N ; -152.27348°E

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    Maupiti ("the Stuck Twins'') is a diamond-shaped island located in the western part of the Society archipelago in French Polynesia. The present study focuses on the data recovered over a single cross-barrier transect located in the south-west barrier during the MAUPITI HOE field campaign, from 5 to 18 July 2018. The studied area is representative of the reef structure observed along the 4km-long southwestern barrier reef, showing an alongshore-uniform structure exposed to swell approaching with weak incident angles, a healthy reef colony. In the cross-barrier direction, the reef displays a clear partitioning of bottom roughness that ranges from low-crested compact structures at the reef crest to higher and sparser coral bommies on the backreef. The experimental setup was specifically designed to analyse and differentiate the dynamics over three roughness-contrasting sections found over the barrier reef. The scientific objectives of the project MAUPITI HOE are to understand the hydrodynamics of an archetypal reef-lagoon system of a high volcanic reef island. The physical functioning of the hydrosystem involves a fine coupling between water levels, waves (including wind, infragravity and VLF waves), currents and seabed structure (reef roughness). Four pressure sensors (OSS3, OSS4, OSS5, OSS6) have been deployed across the reef flat/ backreef, outside the surf zone. The bottom pressure is measured continuously at 10 Hz, and are converted into free surface elevation assuming hydrostaticity. An electrocurrent meter S4 provides the wave forcing while AQP1 is a velocity profiler providing the transports. The bed profile is obtained from the combination of (I) boat survey in the deeper part and (ii) high resolution GNSS RTK topography by feet. Two datasets are available: one is concerning the mean parameters linked to the reef barrier dynamics, and the second dataset is concerning the wave friction.