France

This page is dedicated to french scientific projects to whom Coriolis data centre (DAC) provide the decoding , realtime Quality control and distribution services.

 

Please click on the left menu projects titles to access each project page (you can also click the "read more" links below )

 

NAOS

Novel Argo Ocean observing System

 

Coordinator: Pierre-Yves le Traon (Ifremer Brest)Project leaders at LOV: Fabrizio D'Ortenzio & Hervé Claustre

 

 

 

In order to better forecast effects of climate change, and to address within this context the possible consequences on Ocean functioning, it is necessary to continuously guarantee a global view relying on high-quality data acquisition on oceanic properties.

 

 

 

As a French initiative, the NAOS project contributes significantly to an international network called Argo. The latter maintains a fleet of profiling floats, basically equipped with physical sensors (temperature and salinity) that provide measurements of the Ocean interior (until ca. 2000 meters depth). Besides the contribution to Argo, NAOS will prepare the future. New floats with extended capabilities (e.g. deeper profiling, under-ice observations) will be developed. Furthermore, the ongoing developments at the OAO/LOV with respect to biological and biogeochemical floats will be strongly reinforced. As part of NAOS, OAO/LOV will focus on two key areas: the Arctic Ocean (collaboration with the Canada Excellence Research Chair, CERC, in Remote Sensing of Canada’s New Arctic Frontier, UMI Takuvik) and the Mediterranean Sea.

 

 

 

NAOS takes part in the program “Investissements d’avenir”, i.e. the French governmental call “Equipements d’Excellence (EQUIPEX) 2010”, operated by the National Research Agency (ANR).

Coriolis DAC

Coriolis is a Data Assembly Centre (DAC) for French and some Europeans Argo projects.

 

The role of a DAC is to collect, decode, control and distribute data from more than 200 profiling floats from 7 countries and 11 scientific projects. Coriolis manages 3 families of floats (Provor, Metocean, Apex) with a total of 17 different versions.

 

All float data managed by Coriolis DAC are distributed in real-time on ARGO GDAC (Global Data Assembly Centre) and GTS (the WMO global network) by way of Météo-France.

Cirene

The CIRENE Project aims at deploying PROVOR floats in the western Indian Ocean. It is integrated into the french contribution to the ARGO Programme.

 

Between 5°N and 10°S, PROVOR floats have been deployed at different longitudes allowing a better zonal coverage of the Indian Ocean thermohaline variability in order to address the equatorial variability (e.g. impact of the Wyrtki Jets, Dipole Mode, ENSO impact), the SST/thermocline decoupling below the wind convergence zone, and the role of the ocean into boreal winter Intraseasonal Oscillation characteristics.

Scientific contact : Jérôme Vialard jv@lodyc.jussieu.fr

Congas

(CONtinental GAScogne) is a joint SHOM and LPO/CNRS project (2004-2006).

 

Several types of lagrangian instruments (SURface DRIFTers, MARVOR and RAFOS acoustic floats, PROVORS-T profiler floats) are being used in order to study the lagrangian circulation and hydrology over the continental slope and adjacent abyssal plain of the Bay of Biscay. Some specific processes, like mesoscale eddies or slope currents, will be investigated.

Contacts :Alain Serpette (SHOM) Loïc Gourmelen (SHOM) Bernard Le Cann (CNRS)

Data Contact : codac@ifremer.fr

Egypt

ETO-BB

ETO-BB is a joint project from SHOM and IRD.(France)

 

During the Beautemps Beaupre ETO cruise, Argo floats have been launched (may 2003)

 

The PROVOR profiles will be particularly useful in the framework of climate studies in the equatorial and tropical Atlantic, as the CLIVAR Tropical Atlantic Variability program (TAV), and EGEE/AMMA. Particularly, the temperature/salinity profiles allow the study and analysis on the mixed layer characteristics (temperature, salinity, depth) that contribute to govern the heat and water exchanges between the ocean and the atmosphere at the interface.

They also allow to follow the T/S properties and their evolution within the different water masses (surface, central, intermediate waters). Furthermore, the T/S profiles will be used for assimilation in the numerical models, in the framework of operationnal oceanography (especially the MERCATOR program).

Scientific contact : Bernard.Bourles@ifremer.fr
Data management contact : codac@ifremer.fr

Prosat

PI: Louis Prieur
Data management contact :codac@ifremer.fr

Flops

PI: Alexis Chaigneau
Data management contact :codac@ifremer.fr

Flostral

FLOSTRAL is a joint-project from LEGOS, LBCM, UBO and LODYC French research centers to deploy an array of PROVOR profiling floats in 2003-2004 in south west Indian ocean. Flostral will monitor and quantify the circulation of AAIW and SAMW waters.

Contacts :
Rosemary MORROW, LEGOS,
Nicolas METZL, LBCM,
Sabrina SPEICH, UBO,
Gurvan MADEC, LODYC

Frontalis

The FRONTALIS-3 cruise in April – May 2005

 

A French contribution to ARGO deployments in the western tropical Pacific

 

On average, the distribution of near-surface water in the equatorial Pacific presents warm (>28°C) and low salinity (<34.5) waters in the so-called warm and fresh pool. The eastern edge of the warm pool is dominated by strong interannual zonal displacements related to the El Niño Southern Oscillation (ENSO) event. It is most often characterised by a well-marked zonal front in surface salinity, partial pressure of CO2, concentration of nutrients and plankton. Such zonal front is the result of a zonal convergence of western and central Pacific water masses. The zonal front is connected with changes in mixed-layer temperature and salinity, with barrier-layer thickness, formation and variability, as well as with the location of the world's largest tuna harvest. The zonal displacements of the front induce an extension (El Niño) or a reduction (La Niña) of the surface waters above 28°C, the temperature threshold for organised atmospheric convection. Hence, they are the main source for the ENSO coupled system.

The FRONTALIS-3 cruise, conducted on board the IRD R/V l'Alis during April 22 – May 20 (Fig. 1) in the western tropical Pacific ocean, carried on physical (CTD, L-ADCP, S-ADCP, TSG, drifting buoys) and biochemical (NO2, NO3, PO3, pCO2, plankton, chla) observations on this zonal front in order to analyse the mechanisms responsible for its formation, its persistence and potential role in the ENSO air-sea interaction coupled system. During the cruise, we farther repeated the sampling of the 165°E meridional section in order to study a) the time-variability of the water masses between 0 and 2000 m and b) the ventilation of the thermocline waters by the subtropical waters, which is thought to be one possible mechanism at the origin of a decadal variability of the ENSO phenomenon. This 165°E section has been sampled regularly during 1984-2000, within 0-1000m. It represents one of the longest time series of repeated hydrographic sections in the open ocean.

A total of 20 PROVOR floats were also launched during that cruise (Fig.2), with 10 floats along the equator within 161°E and 172°E, and 10 floats along 165°E within 19°S and 10°S. In line with the CLIVAR (www.clivar.org) objectives, these floats will enable us, for the first time, to monitor the eastern edge of the warm pool during a rather long time period, depending on the drifter drifts at depth, as well as to initiate continuous measurements of the southern route of the possible thermohaline anomalies related to the low frequency modulation of ENSO.

PI: Thierry Delcroix (IRD Toulouse) & Christophe Maes (IRD Nouméa)
Data management contact: codac@ifremer.fr