A5076619315- Marine and coastal ecosystems
- Arctic and Antarctic ice dynamics
- Marine Biology and Ecology Research
- Oceanographic and Atmospheric Processes
- Atmospheric and Environmental Gas Dynamics
- Advanced NMR Techniques and Applications
- Methane Hydrates and Related Phenomena
- Atomic and Subatomic Physics Research
- Climate change and permafrost
- Coral and Marine Ecosystems Studies
- Calibration and Measurement Techniques
- Isotope Analysis in Ecology
- Ocean Acidification Effects and Responses
- Water Quality Monitoring and Analysis
- Cryospheric studies and observations
- Quantum, superfluid, helium dynamics
- Solid-state spectroscopy and crystallography
- Oil Spill Detection and Mitigation
- Water Quality Monitoring Technologies
- Marine and environmental studies
- Icing and De-icing Technologies
- Arctic and Russian Policy Studies
- Impact of Light on Environment and Health
- Underwater Acoustics Research
- Environmental Monitoring and Data Management
Sorbonne Université
2015-2025
Laboratoire d’Océanographie de Villefranche
2016-2025
Centre National de la Recherche Scientifique
2015-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2002-2006
Service de Physique de l'État Condensé
2003-2006
CEA Paris-Saclay
2002-2006
The Biogeochemical-Argo program (BGC-Argo) is a new profiling-float-based, ocean wide, and distributed monitoring which tightly linked to, has benefited significantly from, the Argo program. community recommended for BGC-Argo addition of six measurements in to pressure, temperature salinity measured by Argo, include oxygen, pH, nitrate, downwelling light, chlorophyll fluorescence optical backscattering coefficient. purpose this enable biogeochemistry health, particular, monitor major...
Autonomous and cabled platforms are revolutionizing our understanding of ocean systems by providing 4D monitoring the water column, thus going beyond reach ship-based surveys increasing depth remotely sensed observations. However, very few commercially available sensors for such capable large particulate matter (100-2000 μm) plankton despite their important roles in biological carbon pump as trophic links from phytoplankton to fish. Here, we provide details a new, scientific camera-based...
Abstract Characterizing phytoplankton distribution and dynamics in the world's open oceans requires situ observations over a broad range of space time scales. In addition to temperature/salinity measurements, Biogeochemical‐Argo (BGC‐Argo) profiling floats are capable autonomously observing at high‐frequency bio‐optical properties such as chlorophyll fluorescence, proxy concentration (Chl ), particulate backscattering coefficient (b bp stock organic carbon, light available for...
Abstract. As commonly observed in oligotrophic stratified waters, a subsurface (or deep) chlorophyll maximum (SCM) frequently characterizes the vertical distribution of phytoplankton Mediterranean Sea. Occurring far from surface layer “seen” by ocean colour satellites, SCMs are difficult to observe with adequate spatio-temporal resolution and their biogeochemical impact remains unknown. Biogeochemical-Argo (BGC-Argo) profiling floats represent appropriate tools for studying dynamics SCMs....
Abstract In 2013, as part of the French NAOS (Novel Argo Oceanic observing System) program, five profiling floats equipped with nitrate sensors (SUNA‐V2) together CTD and bio‐optical were deployed in Mediterranean Sea. At present day, more than 500 profiles physical biological parameters acquired, significantly increased number available data Results obtained from confirm general view basin, well‐known west‐to‐east gradient oligotrophy. seasonal scale, north western displays a clear...
The necessity of wide, global-scale observing systems for marine biogeochemistry emerged dramatically in the last decade. A global network based on Biogeochemical (BGC) Argo floats is considered as one most promising approaches reaching this goal. As a first step, pilot studies were encouraged to test feasibility BGC-Argo array, consolidate methods and practices under development, set up array's characteristics. study Mediterranean Sea—deemed suitable candidate case because it combines...
Despite polar night and thick sea ice, algae can grow in the wintertime Arctic Ocean.
Monte Carlo simulations are used to explain and quantify the errors in inherent optical properties (IOPs) (absorption attenuation coefficients) measured using WET Labs AC-9 submarine spectrophotometer, assess correction algorithms. Simulated samples with a wide range of IOPs encountered natural waters examined. The relative on absorption coefficient general lower than 25%, but reach up 100% highly scattering waters. Relative coefficients more stable, an underestimation mainly driven by...
Abstract. Since 2012, an array of 105 Biogeochemical-Argo (BGC-Argo) floats has been deployed across the world's oceans to assist in filling observational gaps that are required for characterizing open-ocean environments. Profiles biogeochemical (chlorophyll and dissolved organic matter) optical (single-wavelength particulate backscattering, downward irradiance at three wavelengths, photosynthetically available radiation) variables collected upper 1000 m every 1 10 days. The database 9837...
Monte Carlo simulations are used to compute the uncertainty associated light backscattering measurements in turbid waters using ECO-BB (WET Labs) and Hydroscat (HOBI scattering sensors. provide an accurate estimate of particulate volume coefficient after correction for absorption along short instrument pathlength. For measurements, because a longer photon pathlength, both effects must be corrected for. As standard (sigma) potentially leads large errors, improved method is developed then...
Abstract. The Green Edge initiative was developed to investigate the processes controlling primary productivity and fate of organic matter produced during Arctic phytoplankton spring bloom (PSB) determine its role in ecosystem. Two field campaigns were conducted 2015 2016 at an ice camp located on landfast sea southeast Qikiqtarjuaq Island Baffin Bay (67.4797∘ N, 63.7895∘ W). During both expeditions, a large suite physical, chemical biological variables measured beneath consolidated sea-ice...
Abstract In the eastern Mediterranean Sea, satellites have observed events of spring surface‐chlorophyll increase in Rhodes Gyre region recurring intermittently. Few situ biogeochemical data, however, exist to confirm their consistency, elucidate seasonal characteristics, or discriminate among possible drivers. During year 2018, an array BGC‐Argo floats was deployed region, collecting first‐ever annual time series profiles parameters this area. Their observations demonstrated that nitrates,...
Abstract Photosynthetic available radiation (PAR) is the light usable by photosynthetic organisms. measurements at depth are required to quantify availability for primary production. Direct PAR may be measured with full‐spectrum quantum sensors range 400 700 nm. When spectrally resolved measured, as downwelling irradiance spectrum , computed numerically integrating within those limits. As varies across a spectral continuum, needs sufficiently large number of bands, provide an unbiased...
Climate Change is the biggest environmental challenge of 21st century. Novel sensors are needed to improve our understanding carbonate chemistry and a concerted scientific effort compile different requirements, such as needs know how carbon observations measured from various parts oceans differs. ICOS, EURO-ARGO EMSO ERICs all open accessible world-class sustainable research infrastructures, with enhanced international cooperation that crucial foster innovation in field which have joined...
The international BioGeoChemical-Argo program recommends the measurement of 6 essential ocean variables (EOVs), one which being inorganic carbon. Estimates pH variation in open using traditional sampling methods show a decrease 0.002 units per year [1]. Understanding and predicting variations precise, certified situ detection over oceans around world long term is currently essential. In frame PIANO (Plan d’Investissement Argo Nouvelles Observations, Ifremer) project we designed developed new...
The high seas, which constitute about two-thirds of the ocean, have long been regarded as a shared resource and responsibility for global community. They offer crucial services such climate regulation by absorbing heat carbon dioxide, ensuring food security, providing habitats diverse species, supporting rich marine biodiversity. However, increasing anthropogenic pressures change threaten these services. Moreover, some mitigation strategies, Carbon Dioxide Removal (mCDR) are being proposed...
An efficient system to produce in situ high quality radiometric measurements is compulsory rigorously perform the vicarious calibration of satellite sensors dedicated Ocean Color Radiometry (OCR) and validate their derived products. This requirement especially needed during early stages an OCR activity or for remote areas poorly covered by oceanographic cruises with possible bio-optical anomalies. Taking advantage Argo's profiling float, we present a new autonomous float measurements. The...
The vertical diffuse attenuation coefficient for downward plane irradiance ( K d ) is an apparent optical property commonly used in primary production models to propagate incident solar radiation the water column. In open water, estimating relatively straightforward when a profile of measurements irradiance, E , available. Arctic, ice pack characterized by complex mosaic composed sea with snow, ridges, melt ponds, and leads. Due resulting spatially heterogeneous light field top meters...
Optical Earth observation satellites provide vast amounts of data on a daily basis. The top-of-atmosphere radiance measured by these is usually converted to bottom-of-atmosphere or reflectance which then used for deriving numerous higher level products monitoring environmental conditions, climate change, stock natural resources, etc. increase available remote sensing impacts decision-making both regional and global scales, demands appropriate quality control validation procedures. A...
Scattering phase functions derived from measured (volume-scattering meter, VSM) volume-scattering (VSFs) Crimean coastal waters were found to have systematic differences in angular structure Fournier-Forand (FF) with equivalent backscattering ratios. Hydrolight simulations demonstrated that the of VSF could result variations modeled subsurface radiance reflectances up +/-20%. Furthermore, between VSM and FF simulated be nonlinear as a function scattering not explained single-scattering...
We report the first measurements of scattering coefficient natural marine particles, which extend over near-infrared spectral region to up 870 nm.The were conducted in three different European estuaries (Gironde, Tamar and Elbe) using an situ absorption attenuation-meter.The observed particulate coefficients varied from 1 nearly 100 m -1 .The shape very closely matched a λ -γ dependence, is expected when particle size followed power-law distribution.The slope spectrum, γ, spanned 0.1 1.2...
Abstract. The MALINA oceanographic campaign was conducted during summer 2009 to investigate the carbon stocks and processes controlling fluxes in Mackenzie River estuary Beaufort Sea. During campaign, an extensive suite of physical, chemical biological variables were measured across seven shelf–basin transects (south–north) capture meridional gradient between open ocean. Key such as temperature, absolute salinity, radiance, irradiance, nutrient concentrations, chlorophyll a concentration,...
Abstract Miniaturized radiance cameras measuring underwater multispectral radiances in all directions at high-radiometric accuracy (CE600) are presented. The camera design is described, as well the main steps of its optical and radiometric characterization calibration. results show excellent quality specifically designed fish-eye objective. They also low noise linearity complementary metal oxide semiconductor (CMOS) detector array that used. Initial obtained various oceanic environments...