BGC-Argo

BGC-Argo BGC-Argo

The Biogeochemical-Argo (BGC-Argo) project supports the French contribution to the establishment of the global network of biogeochemical profiling floats of the international BGC-Argo program, whose scientific and implementation plan was published in 2016 (pdf link).

In practice, this involves acquiring bio-optical sensors, calibrating them and implementing them on Argo profiling floats distributed to the national community as part of the LEFE-GMMC call for tenders. The BGC-Argo floats are equipped with biogeochemical and bio-optical sensors capable of measuring oxygen, nitrate, chlorophyll, suspended particles, pH, illumination available for photosynthesis and irradiance at certain wavelengths. More information on the BGC-Argo website about these measures and their justification.

This project, led by LOV researchers (IMEV), therefore also aims to promote the appropriation of these new observation technologies within the national community to serve an emerging need. It is also to provide the concerned national teams with support for the deployment of floats, their management (i.e. communication), quality control (QC), accessibility to Chlorophyll-a data and matchups and other satellite products associated with the emergence of the floats. More generally, this request is part of the SNO Argo-France, SOERE CTD-O2, ERIC Euro-Argo, follows the recommendations of the International Ocean Colour Coordinating Group (IOCCG, 2011) and now the international BGC-Argo program.
Within the ODATIS Ocean Pole, BGC-Argo data are distributed by CDS-IS-Coriolis in collaboration with the teams of CDS-IS-IMEV.

The data made available are vertical profiles from 0 to 1000m in :

Marine biogeochemistry

  • Fluorescence of the CDOM;
  • Oxygen concentration;
  • Optionally and depending on the implementation, other additional sensors perform measurements of nitrate concentrations and, in the near future, pH.

Ocean Physics

  • pressure;
  • temperature;
  • salinity;
  • chlorophyll a fluorescence;
  • backscatter coefficient at 700 nm;
  • downward irradiance at 3 wavelengths (380, 412, 490 nm);
  • as well as the light available for photosynthesis (PAR) integrated over the 400-700 nm spectral range.

Parameters measured according to the sensors present on BGC-Argo floats

FluorescenceChlorophyll concentration

Backscattering

Suspended particles / Particulate Carbon Concentration
PARPhotosynthetic Available Radiation
Radiometry
(380, 412, 490 nm)
Downward brightness at specific wavelengths
CTDSalinity, temperature, depth
SUNANitrate concentration
OPTODE O2Oxygen concentration
Deep-Sea ISFETpH

Float trajectory map

The trajectories of the floats already deployed and the visualization of the associated measurements are accessible on an interactive graphical interface.

In-situ floats and remote sensing

Comparisons between float measurements and satellite measurements of ocean color are available in real time on a graphical interface (project Bio-Argo France).

Qualified data can be accessed from the FTP server: ftp://ftp.ifremer.fr/ifremer/argo

Scientific publications

  • Lavigne, H., et al. (2012). Towards a merged satellite and in situ fluorescence ocean chlorophyll product. Biogeosciences, 9(6), 2111-2125. doi:10.5194/bg-9-2111-2012.
  • Organelli, E., et al. (2016). A Novel Near-Real-Time Quality-Control Procedure for Radiometric Profiles Measured by Bio-Argo Floats: Protocols and Performances. Journal of Atmospheric and Oceanic Technology, 33(5), 937-951. doi:10.1175/jtech-d-15-0193.1.
  • Organelli, E., H. Claustre, A. Bricaud, M. Barbieux, J. Uitz, F. D'Ortenzio, and G. Dall'Olmo (2017). Bio‐optical anomalies in the world's oceans: An investigation on the diffuse attenuation coefficients for downward irradiance derived from biogeochemical Argo float measurements. Journal of Geophysical Research-Oceans, 122, 3543-3564. doi:10.1002/2016JC012629.
  • Organelli, E., et al. (2017). Two databases derived from BGC-Argo float measurements for biogeochemical and bio-optical applications at the global scale. Earth System Science Data Discussions. doi:10.5194/essd-2017-58.
  • Rembauville M., Briggs N., Ardyna M., Uitz J., Catala P., Penkerc’ch C., Poteau A., Claustre H., Blain S. (2017) Plankton assemblage estimated with BGC-Argo floats in the Southern Ocean : implications for seasonal successions and particle export . Journal of Geophysical Research, doi:10.1002/2017JC013067
  • Sauzède, R. et al. (2016). A neural network-based method for merging ocean color and Argo data to extend surface bio-optical properties to depth: Retrieval of the particulate backscattering coefficient. Journal of Geophysical Research-Oceans, 121, 2552–2571. doi:10.1002/2015JC011408.

Partners' roles

  • CNES : acquisition of optical sensors, transformation of Argo floats into BGC-Argo floats, and cost of data transmission to shore.
  • CORIOLIS : profiling floats and their qualification, data distribution platform.
  • INSU-CNRS-SU (LOV and OSU Ecceterra) : sensors integration on floats, sensor and data qualification procedure, data access, file reading tools (NetCDF), possible scientific support.

External websites and reports

Contacts