Oceanographic cruise “SWINGS” (South Indian Ocean GEOTRACES Section)

The SWINGS (South West Indian Geotraces Section) sea campaign has just ended aboard the Marion Dufresne II. Back on this scientific expedition which took place from 11th January to 9th March 2021.

Supported by ISblue, ANR, FOF and CNRS, Hélène Planquette, marine bio geochemist at IUEM and Catherine Jeandel, Toulouse geochemist oceanographer, both researchers at CNRS, led this expedition in the southern ocean with 46 scientists many nationalities: French, American, South African, English, Swiss…They have studied more precisely how chemical species essential to the development of life are brought there, transformed, transported by currents and sedimented in the abyss.

The ocean retains CO2 from the atmosphere either physically, with simple dissolution, or biologically through photosynthesis of phytoplankton. One of the objectives of SWINGS was to evaluate the activity of these microorganisms whose development depends on the presence of chemical elements at very low concentrations. These elements were the main target of SWINGS.

Credit : Sybille d’Orgeval

Alongside the researchers, various scientific professions and specialties are mobilised: engineers, technicians, chemists, geologists, biologists, climatologists, physicists… Nevertheless, artists were also present on the ship. Sybille d’Orgeval and Laurent Godard will make a documentary in which they wish to add an important touch of humanism to this race for knowledge.

SWINGS is part of the global GEOTRACES programme, which since 2010 has been building a chemical atlas of the oceans. The biogeochemical cycles of carbon and nitrogen are studied; trace elements and their isotopes are quantified. These data are acquired according to very strict protocols, compared and validated between the different countries and made available in “open source” in a database.

More information :

SWINGS Cruise Blog

Isle of Heard. Credit : Corentin Clerc

Article source – copublication CNRS Le journal & Exploreur .