Polar ocean and atmosphere: large scale vortex dynamics

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The oceans and atmosphere have general circulation, and yet are rich with flow fields and density fields of much smaller scale. My overall research objective is to better understand the dynamical processes that govern the behavior of the stratified and rotating fluids that comprise the Earth's oceans. This study will enhance our capability to predict the evolution of complex nonlinear fluid dynamical systems. During the next grant period I propose to continue this work in order to deepen our understanding of large and small-scale vortical phenomena in oceanic flows.The main objective of this proposal is to investigate circulations on a polar beta-plane which models the quadratic variation of the Coriolis parameter in the polar ocean or atmosphere. The particular focus is on the production of jet-like currents, vortices and Rossby waves. The approach includes theory, numerical simulations and laboratory experiments. In the laboratory we use a new method of remotely measuring pressure, velocity and vorticity in a rotating fluid. We call this new technique 'Altimetric Image Velocimetry', as it uses the parabolic fluid surface as a Newtonian telescope to detect small scale perturbations of the surface. This method can provide high resolution velocity field such that laboratory experiments equal or exceed current 3D numerical models in detailed rendering of the flow. The outcome 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 method is new and can provide the cutting edge research here in Canada.