Turbulent oceans and atmospheres of the rotating planets

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Have you ever wondered why climate is extremely difficult to predict? One of the major reasons is that the components of the climate system such as the Earth's oceans and atmosphere are nonlinear and inherently chaotic. The overall goal of my research program is to better understand the dynamical processes that govern the nonlinear behavior of the stratified and rotating fluids that comprise the oceans and atmosphere. The same processes are often relevant for atmospheres of other planets including gas giants Jupiter and Saturn. This study will enhance our capability to predict the dynamics and evolution of these complex nonlinear fluid dynamical systems. The oceans and atmosphere have a general large-scale circulation, and yet are rich with flow fields and density fields of much smaller scale. The flows are turbulent and contain eddies in abundance. The eddies interact with planetary-scale (Rosby) waves which are due to rotation and curvature of the planet. These motions influence biological production, mixing, and dissipation of momentum in the ocean but the details of their dynamics including their sources and life-cycle are yet to be fully understood. This research program focuses on the production of jet-like currents, eddies and Rossby waves. Our approach combines theory, numerical simulations and laboratory experiments. We use a new laboratory technique that we developed to remotely measure pressure, velocity and vorticity in a rotating fluid. We call this technique 'Altimetric Imaging Velocimetry' and it is not unlike satellite altimetry which revolutionized physical oceanography with the launch of the first satellite altimeters in the early 1990s. Laboratory altimetry provides high resolution velocity field such that laboratory experiments equal or exceed current 3D numerical models in detailed rendering of the flow. The results of the research using this method will be of great interest for communities involved in addressing 'spontaneous imbalance' or 'jets and annular structures in geophysical fluid dynamics' who are working to include non-geostrophic dynamics in what traditionally have been quasi-geostrophic idealizations of ocean and atmosphere. This technique, that we have developed and are continuing to explore and apply, enables cutting edge research here in Canada. This research will yield new results on and understanding of nonlinear dynamics of turbulent oceans and atmosphere.