Influence du couplage océan-atmosphère sur le bilan énergétique de l’océan

The ocean receives energy from the sun and winds. Some of the ocean’s energy is dissipated at small scale and some is returned to the atmosphere as heat. While this general idea is well accepted in the scientific community, the detailed pathways of the energy from one end of the chain to the other are less clear. In particular, internal ocean dynamics plays a fundamental role here by redirecting the energy received from the atmosphere towards fine scales (dissipation route : the direct cascade) or large scales (for a possible redistribution to the atmosphere or a dissipation on the ocean floor : the inverse cascade).

A research team led by the MEOM group is planning to carry a high-resolution coupled ocean-atmosphere simulation in spring 2020 as part of a numerical challenge. The goal of the internship is to conduct a pioneering study that will pave the way for the analysis of this coupled simulation : the objective is to study how energy exchanges at the air-sea interface changes the way the ocean redistributes energy between scales. In practice, we will produce coupled ocean-atmosphere simulations with a simplified model of oceanic and atmospheric dynamics and carry out the first energy diagnostics. These diagnostics are spectra of kinetic and potential energy and analysis of energy transfers between the different scales. This study is based on the works of O’Rourke et al (2018) and Martin et al (2019), who made similar diagnoses for the temporal cascade only. Depending on the student’s interest, one can then move on to other numerical simulations of forced and coupled oceanic turbulence or use theoretical tools of turbulence to understand the mechanisms that have been observed in the simulations.

Pour candidater : Adresser un CV et une lettre de motivation par email à l’adresse ci-dessous : Thierry.Penduff cnrs.fr