Energy Pathways and Structures of Oceanic Eddies in the ECCO2 State Estimate and Simplified Models

Ru Chen, Ph.D, 2013
Carl Wunsch, Advisor

Studying oceanic eddies is important for understanding and predicting ocean circulation and climate variability. The central focus of this dissertation is the energy exchange between eddies and mean flow and banded structures in the low-frequency component of the eddy field. A combination of a realistic eddy-permitting ocean state estimate and simplified theoretical models is used to address the following specific questions. (1) What are the major spatial characteristics of eddy-mean flow interaction from an energy perspective? Is eddy-mean flow interaction a local process in most ocean regions? (2) The banded structures in the low-frequency eddy field are termed striations. How much oceanic variability is associated with striations? How does the time-mean circulation, for example a subtropical gyre or constant mean flow, influence the origin and characteristics of striations? How much do striation contribute to the energy budget and tracer mixing?