Comprehensive ocean general circulation models that simulate large scale flows must incorporate the effects of smaller scale turbulence that cannot be resolved numerically. These effects are nonlinear and thus are difficult to capture. This project will focus on how mesoscale eddies interact with the large scale and in particular what the effect of randomness and transience of the eddy field is on the mean flow. The central problem that will be tackled is how large scale currents are generated by these interactions. In the ocean, this process is ubiquitous.
In this project, a scientist from Woods Hole Oceanographic Institution will treat these eddy effects as stochastic processes. The primary objective of this proposal is to gain a physical understanding of the mechanics behind the response of these stochastic forcings. In particular, this will allow him to consider "up gradient" fluxes which can not be handled by eddy viscosities, which are commonly used in circulation models. This novel approach carries an element of risk that it will not be successful.
The study potentially has very important broader impacts because it will provide a physical basis for a new means of parameterizing turbulence in ocean circulation models and thus climate models which should improve their performance.
