Oceanic turbulence regimes and their impact on the climate system

Abstract: The ocean absorbs most of the heat and about a quarter of the carbon emissions caused by human activities. These anthropogenic perturbations significantly influence the ocean circulation, with direct and critical implications for the climate system. The ocean circulation is characterized by diverse turbulence regimes that span a vast range of spatial and temporal scales. Understanding how these distinct turbulence regimes and their interactions lead to the observed spatiotemporal distributions of energy, heat, and tracers in the ocean is essential for predicting circulation adjustments and their effects on the climate system. 
In this talk, I will discuss how the interplay between geostrophic turbulence, submesoscale turbulence, boundary layer turbulence, and wave turbulence shapes the ocean circulation, with a particular focus on energy transfer and material transport. I will also distinguish between the dominant processes occurring in the ocean’s mixed layer, where continuous interactions with the atmosphere take place, and in the deeper thermocline region. Finally, I will demonstrate how a comprehensive approach – combining analytical theory, circulation models of varying complexity, remote sensing, and carefully designed field experiments – can ultimately improve the representation of these turbulent processes in climate models.