Measuring the Mesoscale/ Sub-Mesoscale Eddy Cascade in the ARCTERX Region
Abstract
The eddy-rich region of the NW Pacific Ocean extending from Palau into the South China Sea is known for very energetic processes an d extremes in atmospheric forcings. The problem at hand, namely the quantification of the turbulent eddy exchange throughout this r egion from the mesoscale field to the feature rich sub-mesoscale velocity field, is elusive and not treatable with a purely modelin g approach. In-situ observations are needed for model validation, and wherever possible, for data assimilation. We propose a Lagran gian experiment that uses water-following, satellite-tracked Surface Velocity Program (SVP) drifters drogued at 15 m depth to direct ly measure the surface kinetic energy at the sub-mesoscale (1-10km). We envision the deployment of four large arrays of 50 Lagrangi an drifters each, designed to resolve a variety of spatial and temporal scales, ranging from ~100 km to a few km (sub-mesoscale). We plan to operate during the two seasons when the eddy kinetic energy levelsare largest, that is, during the summer and the winter mo nsoons. The two concurrent dense arrays of drifters will be deployed using two different ships. Our preferred locations are the Sout h China Sea, between Kaohsiung and DongSha Atoll, and the region between Palau and Guam. Our approach, combined with satellite altim etry data, will allow the computation of both eddy kinetic energy at a range of spatial scales, mesoscale and sub mesoscale, and of the calculation of momentum and vorticity fluxes using established methodologies. These quantities will be compared to results from numerical models and will ultimately help in assessing and improving the model parameterizations of energy at meso and, wherever po ssible, sub-meso scales. We will work with the selected teams to design a shared observational strategy. The proposing PI has worke d in the region since 2002 and has collected a Lagrangian drifter dataset that will constitute one of the starting points to help d efine our observational approach. Approved for public release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 07, 2021
- Source ID
- N000142112793
Entities
People
- Luca Centurioni
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego