Théories de la circulation océanique generale et equatoriale

Présentation

Ce cours traite des processus physiques qui controlent l'hydrodynamique de la circulation oceanique generale. Une approche GFD permet de generaliser a d'autres cas, les processus physiques etudies ici, en utilisant des nombres adimensionnels similaires. En effet, nombre de ces processus existent dans l'atmosphere

This is a course about the physical processes which control the hydrodynamics of the open ocean circulation. A GFD approach allows to export elsewhere the physical processes learned herein if the governing adimensional numbers are in the same range. Indeed many of these processes are also active in the atmosphere.

Pré-requis nécessaires

dynamique des fluides geophysiques

Geophysical Fluid Dynamics

Compétences visées

comprendre la circulation generale des oceans et son role dans la variabilite climatique

maitriser les theories fondamentales de la circulation oceanique et etre capable des les utiliser pour valider les resultats d'un modele numerique

understanding the general circulation of the ocean and its role in climate variability

mastering the basic theories of ocean circulation and being able to use them to validate the results of a numerical model

Descriptif

1. Questions to be asked and Basic approximations: geostrophy and hydrostatics

The ocean as a homogeneous fluid

2. Wind driven ocean circulation, Sverdrup theory

3. Potential vorticity, Quasi-geostrophy, Western intensification and western boundary currents

4. Rossby waves

5. Nonlinear inertial effects, Barotropic instability

The ocean as a stratified fluid

6. Quasi geostrophy again

7. Modal decomposition, Rossby waves again

8. The spin up of the wind driven ocean circulation and Gill’s catastrophy

9. The vertical structure of the wind driven circulation (the ventilated thermocline and Rhines-Young’s ideas)

10. Baroclinic instability

11. The thermohaline circulation, The vertical mixing problem, Stommel-Arons’s type ideas for the abyssal circulation, The shut down of the circulation.

 

Tropical and Equatorial Dynamics

- Tropical thermocline ventilation

- Theory of the Equatorial Under Currents circulation

- Equatorial Waves and adjustment

- Tropical ocean-atmosphere coupling : ENSO theories

 

Bibliographie

ACdV Lecture notes Oceanic Circulation (in French)  stockage.univ-brest.fr/~acolindv

Gill, Atmosphere-Ocean dynamics

Pedlosky’s books (The ocean circulation and his GFD book)

Holton, Dynamic Meteorology

Langue d'enseignement

anglais