The intellectual merit of this activity rests on the contribution this research will make to improved understanding, and parameterization in models, of eddy transports in the ocean. The goal of the project is the development and implementation of a theoretically supportable parameterization of mesoscale eddies, based on the notion that eddies transport potential vorticity along isopycnals, for use in large-scale ocean models. The methodology to be employed comprises: development of the theory of eddy transport in relevant contexts, based on the transformed Eulerian mean approach; simulation and analysis of the role of eddies in a hierarchy of ocean models of increasing complexity and consequent identification of the role eddies play in the large-scale circulation; and formulation and implementation of a parameterization scheme. Within this formalism, the advective parts of eddy transport are not parameterized, but the transformed circulation (including the advective eddy terms) is the response to forcing by the non-advective eddy transport. Thus far, the methodology has been applied to the relatively simple case of zonal-mean flows, but this will be extended early in the proposed funding period to incorporate three-dimensional time-mean flows, in both idealized and realistic models.
The broader impacts include the contribution an improved eddy parameterization scheme will make to modeling of the ocean circulation and its role in climate. Along the way to this goal, the project will produce other outcomes, especially advances in the theory of eddy transport in the ocean, and improved understanding of the role of eddies in the structure and circulation of the ocean. Each of these outcomes has broader potential impact on the modeling and understanding of the ocean and its role in climate. Research results will be communicated in the usual way, through scholarly journals and at meetings such as AGU and, through exposure of graduate students at M. I. T. to this activity, it will impact the training of graduate students. In addition, at least one postdoctoral scientist will receive training in this very important area.
