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Observe and modelize
the oceanic δ13C varibility

OCEANS-13C project in a few words

The stable isotopic composition of dissolved inorganic carbon (DIC) in the ocean is a useful semi-conservative tracer for various oceanic analysis (e.g. water masses, paleo-circulation) and global carbon studies (constraint for global carbon budget, interpreting anthropogenic carbon). Sampling since the 80s, the spatiotemporal variability of (δ13C-DIC) is still poorly quantified, and consequently this information is poorly used. In this context, the project OCEANS-13C aims to creating at creating a synthesis of (δ13C-DIC) observations to provide an additional constraint in the studies concerning the evolution of the oceanic carbon cycle. This synthesis allow to address the following isues:

i)  Estimate the accumulation of anthropogenic carbon (Cant) and its evolution in relation to the change of the air-sea CO2 flux and to the ocean dynamics

ii)  Evaluate the impact of the natural variability on regional to global carbon budget (change in transport, carbon production and/or export)

iii)  Estimate the seasonal to decadal variability of the surface δ13C and its driving processes to better understand the relationships with the air-sea CO2 flux variability and hence the climate variability (ENSO, SAM, NAO, IOD...) and to better constraint the atmospheric inverse model.

iv)  Compare and validate ocean models (NEMO-PISCES/IPSL)

In that, this project is complementary to the European project CARBOCHANGE, COCOS, and to international program CLIVAR, SOLAS, IMBER, RECCAP.

For more informations :  >> Work in progress   >> Reports   >> Partners

Work in progress

Started in 2010, this project has already allowed:

-   To synthesize δ13C-DIC observations collected in the framework of the French project from the beginning of the 90s in different oceanic region (South Indian Ocean, Soutern Ocean, North and Tropical Atlantic Ocean, Tropical Pacific Ocean)

>> Data bank

-  To describe the seasonal variability of the δ13C and their driving processes in the surface waters of the Southern indian Ocean (Racapé et al.,2010) and of the North Atlantic Subpolar Gyre (Racapé et al., BG 2014)

-   To estiamte the anthropogenic carbon change in the Irminger Basin (Racapé et al., 2013) and in the Southern Indian Ocean (paper in prep) coupling δ13C and DIC observations

-   To compare and validate the model NEMO-PISCES of IPSL lab (work in progress)

Partners involved in the project


-Virginie Racapé (LSCE, Post-doc CEA)

-Claire Lo Monaco (LOCEAN, Phys. Adj. IPSL)

-Nicolas Metzl (LOCEAN, DR2 CNRS)

-Aicha Naamar (LOCEAN, Tech. UPMC)

-Catherine Pierre (LOCEAN, DR1 CNRS)

-Gilles Reverdin (LOCEAN, DR1 CNRS)


-Laurent Bopp (LSCE, CR1 CNRS)

-Philippe Peylin (LSCE, CR1 CNRS)

LOCEAN: Laboratoire d'Océanographie et du Climat Experimentation et Analyses Numériques, Université Pierre et Marie Curie, Paris.

LSCE: Laboratoire des Sciences du Climat et de l'Environnement, Gif/Yvette

The OCEANS13C project is supported by INSU (Institut National des Sciences de l'Univers).

Webmaster: Claire Lo Monaco (contact)

Host : LOCEAN - Editorial director : Anne-Marie Lezine

Last updated: November, 2014

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