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 )

 

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

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.

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

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

Good Hope

A study and monitoring of the Indo-Atlantic connections. A process study and a contribution to CLIVAR - Southern Ocean

 

While the Southern Ocean dynamics is suspected to have a majr role in the global ocean circulation and present day climate, our understanding of its three-dimensional dynamics and variability, and the impact of such variability on the climate system is at best rudimentary.

 

The GoodHope project aims to partilally fill in this knowledge gap by periodic observations along a line betwween the African and the Antartic continents.
The objectives are fourfold:

  • A better understanding of Indo-Atantic interocean exchanges (in term of water masses, heat and fresh water budgets) and their impact on the global thermohaline circulation and present day climate
  • A better understanding oft the interocean exchanges on the local climate of the African continent
  • A monitoring of the variability of particular dynamical features of the Southern Ocean (Antartic Circumpolar current, frontal systems, ...)
  • A study of the local air-sea exchanges in the Agulhas retroflection region)
good hope

 

Monitoring the GoodHope transect ill be accomplished using a combination of the following observational tools: Altimetry, high density XBTs, XCTDs, profiling floats, subsurface floats, drifters, thermosalinographs.

 

Scientific contact : speich@univ-brest.fr Michel.Arhan@ifremer.fr

 

 

 

Gyroscope

GYROSCOPE is a European project for operational oceanography.

Contacts : Yves Desaubies, Walter Zenk
Web site : http://www.ifremer.fr/lpo/gyroscope

On the 8th of December 2003, the conductivity and salinity all Provor floats equiped with a FSI conductivity sensor have been calibrated.
It represents 80 floats and 3892 vertical profiles.

Many tests on PROVOR-FSI floats have shown that salinity measurements are modified by the presence of the damping disk. Due to the characteristics of this damping disk which disturbs the conductivity measurements, the salinity values of the PROVOR-FSI floats need to be corrected by applying a calibration. This step has been done at the Coriolis Data Center for some specific versions of PROVOR-FSI floats which are controlled by the Coriolis DAC.

  • This calibration was done with the following equation : C' = a*C + b,
    Where C is the conductivity, a and b are :
    slope a = 1.000773
    offset b = -0.00495
  • With the new conductivity C', the new salinity S' is computed : S' = f(P, T, C')