Collaborative Proposal: Oceanic Energy Cascade from Global to Regional Predictive Models.
Abstract
ABSTRACT Understanding the cascade of energy injected into the ocean is crucial to developing our knowledge of ocean predictability and dynamics. Steep ridges, islands, and atolls in the ocean scatter waves and convert energy at a variety of scales, from long Rossby waves through mesoscale, sub-?mesoscale, and internal waves. This energy injected at the steep ridges has significant implications for global and regional ocean prediction. Models with insufficient resolution, or which lack the physics of the energy cascade will miss the topographic effects and suffer a drop in predictive skill. These localized effects may play an important role in the basin-?wide circulation that is currently predicted by the Navy’s global HYCOM/NCODA system. We propose a unique multi-?model approach to examine how the cascade of energy and enstrophy impact global and regional predictive skill in the FLEAT region. We will employ two state-?of-?the-?art numerical models nested within the global HYCOM using advanced state estimation techniques to reproduce the flows in the FLEAT region. Our goal is to examine the effects of local energy conversion at and near ridges, how the enstrophy affects local ridge and shelf physics, and how the energy cascade affects lower wavenumbers away from the ridge in the open ocean. By assimilating data at a wide variety of scales into models of varying physics, we will examine how the control vectors account for “mismatches” in resolved energy between island-?scale, medium-?scale regional, and large-?scale global models. The control vector will provide information about how the unresolved information is fed “out” to the global HYCOM model even without online, two-?way nesting. We will collaborate with FLEAT investigators (Drs. Hemantha Wijesekera of NRL, Eric Terrill, Dan Rudnick, and Matthew Alford of SIO/UCSD, Mark Merrifield of UH, and others) to: (i) gain access to a significant variety of data sampled during the program; (ii) provide model estimates of the flow to collaborators to provide context for the observations; and, (iii) work with collaborators to develop ways of representing (via parameterization or other methods) small-?scale processes in the global-?scale models. We will use MITgcm and ROMS, both nested within the US Navy’s global HYCOM model. Lessons learned will be shared with the NRL development group led by Dr. Gregg Jacobs.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2016
- Source ID
- N000141512598
Entities
People
- Bruce D. Cornuelle
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego