École Nationale Supérieure de
Techniques Avancées

Abstract

The vertical density stratification and the meridional temperature gradient in the atmosphere and oceans trigger turbulence through baroclinic instability. Therefore, the heat transport is enhanced which reduces the temperature difference between the poles and the equator. This is the main reason a theory of climate should properly include this mixing. However this turbulence transfers energy to dissipative structures at scales too small for coarse usual models. In this report, the issue studied is the construction of a diffusive closure model describing the heat transport by baroclinic turbulence at large scales. My internship supervisor already developped one using the two-layer quasigeostrophic model assuming the two layers had the same depth. My work was to extend it to arbitrary layer depths.