PAOC Spotlights

The Postdoc, the Elephant Seal and the Antarctic Circumpolar Current.

Mon April 25th, 2011
Helen Hill
Fabien Roquet, is a postdoc working with Carl Wunsch. He is interested in the oceanic circulation, with a special emphasis on the Southern Ocean, collection and analysis of hydrographic data obtained with instrumented elephant seals and the energetics of the general ocean circulation. In this video interview he talks about his thesis work and what he is working on now.


Fabien studied for his PhD in Paris at the Muséum National d’Histoire Naturelle. A particular focus of that work was an observational study over the Kerguelen Plateau in the Southern Ocean. In that region, the topography shallows to within a ~1000 m of the surface over an extended region (~106 km2) creating a pronounced northward perturbation in the local pathway of the Antarctic Circumpolar Current (ACC). 

In the course of his thesis work Fabien became involved in SEaOS, a project in which instrumented elephant seals are employed to collect oceanographic data. Using hydrographic data obtained from elephant seals (coupled with data obtained from traditional transects made from a regular research vessel) Fabien and co-workers were able to measure more accurately the properties of, and confirm trends in, the structure and transport of the narrow but powerful (~40Sv), “Fawn Trough Current” dividing the northern and southern portions of the Kerguelen Plateau. 

Since arriving at MIT, Fabien has been working on a new project studying how wind  activates the ocean circulation, that is, how energy put into the ocean through the action of the wind is transformed into ocean currents. As Fabien explains, “Basically to [make the ocean move] you have to blow on it or change its density at the surface. The question then becomes: In the real ocean, what is the relative role of these two processes? We know that the wind is definitely extremely important but it is much more difficult to say how density fluxes are acting. We know that they are also very important it’s just that they are acting so differently it is difficult to handle them together in the same framework”. In his work Fabien is seeking to develop a deeper theoretical understanding of the ocean’s wind driven circulation by looking at it from an energetic point of view.

Asked what had set him on his path to oceanography, Fabien recounts, “Its a bit funny. [As an undergrad.] I was in an engineering school studying telecommunications and didn’t know anything about the ocean. I was looking for [a summer internship]. The father of a friend was an oceanographer, and so I applied: It turned out to be both an exciting and fascinating field and so I have just carried on. 

Roquet recognises a strong foundation in math and sound programming skills underpin his research: In his work he needs to be able to manipulate and analyse large data sets as well as create and use numerical models of the ocean and atmosphere. The part Roquet says he likes least is writing in English: As far back as he can remember, he recalls everybody telling him “you have to learn English”, “English is so important”. Fabien comments, “It’s lots of work made harder still by the fact that the stereotype (that the kind of  people who like math aren’t so good at language) was definitely true in my case!” As an International Scholar Fabien acknowledges he benefits enormously from the global breadth of PAOC membership noting in particular that coming to PAOC has been like finding “a little bit of France!”  

You can read more about Fabien’s thesis work in Roquet et al., 2009. His most recent paper “On the Patterns of Wind-Power Input to the Ocean Circulation”, co-authored with Wunsch, is  submitted to J. Phys. Oc.