As an oceanographer and marine biogeochemist, my main scientific researches are focused on quantifying the fluxes and processes that govern the chemical state of the ocean.

Since 1987 I have been among the pioneers in developing trace element and isotope analysis methods for seawater and marine particles. These analytical advances have led to important advances in our understanding of 1) Rare Earth Element concentrations and neodymium isotopes that trace water mass circulation and mixing, dissolved-particulate processes, continent-ocean exchange 2) aqueous barium concentrations and their use as a tracer of water masses and productivity 3) Thorium and protactinium isotopes as tracers of deep water ventilation, scavenging and particulate fluxes. Because one single tracer is not always sufficient enough to constrain complex natural systems, I advocate multi-tracer approaches to resolving natural processes.

I have also adopted this approach as the main strategy of the international GEOTRACES program. In collaboration with colleagues of LSCE and LPO, I also incorporated isotope distributions into general circulation models. I am author or co-author of more than 110 peer reviewed articles, more than 330 communications in international conferences or workshops and wrote with M. Roy Barman a book dedicated to marine geochemistry (published in June 2011).

I also edited the books “Le Climat à découvert” and “L’Energie à découvert” with Rémy Mosseri which include about 100 papers by 130 authors on the methodologies in climate research, published in May 2011 and May 2013 respectively. I have supervised 13 Ph-D students who all found employment after their PhD’s. I participated in 15 oceanographic cruises, 6 of these as chief scientist.

I have also been responsible of the management committee of the Toulouse TIMS (Thermo Finningan MAT 261) for the past 20 years and initiated with Mireille Polvé “ISOTRACES” the network of mass spectrometer users.