Multiscale modeling of vertical and horizontal dispersion of material by submesoscale motions in frontal regions
Abstract
Vertical transport from surface to depth in the upper ocean presents a challenge to both measurement and prediction because of its s"mall magnitude, its spatiotemporal intermittency and its uncertain links to environmental forcing. Recent and ongoing work points to" the importance of coherent eddy~driven flow convergences in mediating vertical transport. The vorticity and strain increase as the length scale of the eddying motion decreases towards the submesoscale but the time scale over which the flow field remains coherent also changes with decreasing length scale in a manner that is poorly understood. We propose numerical simulations of frontal regions that are seeded with an ensemble of floats to study the space~time behavior of submesoscale eddies. The associated horizontal and" vertical dispersion of floats will be obtained as a function of frontal strength, stratification and wind forcing. Observational oc""eanographers are aware that float statistics can deviate from truly Lagrangian tracking owing to float inertia, size and background"" stratification. The proposed simulations will help quantify thisdeviation. Both, high~resolution single~grid LES as well as adapti"ve nested~grid simulations with SOMAR~LES will be conducted. SOMAR~LES can take advantage o the spatial sparseness of the submesoscale eddies (the hotspots of coherent vertical transport) to capture vertical transport with high fidelity at reasonable computational cost.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 20, 2018
- Source ID
- N000141812137
Entities
People
- Sutanu Sarkar
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego