Simulation of Deep Cycle Turbulence by a Global Ocean General Circulation Model
Abstract
Deep cycle turbulence (DCT) is a diurnally oscillating turbulence that penetrates into a stratified shear layer below the surface mixed layer, which is often observed in the eastern Pacific and Atlantic above the Equatorial Undercurrent (EUC). Here we present the simulation of DCT by a global ocean general circulation model (OGCM) for the first time. As the k‐ε vertical mixing scheme is used in the OGCM, the simulation of observed DCT structure based on in situ microstructure measurements can be explicitly demonstrated. The simulated DCT is found in all equatorial ocean basins, and its characteristics agree very well with observations. Zonal and meridional variations of DCT in the entire equatorial Pacific and Atlantic are described through constructing the composite diurnal cycle. In the central Pacific where the maximum shear associated with EUC is deep, the separation of DCT from the surface mixed layer is much more prominent than other areas.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 31, 2020
- Source ID
- 10.1029/2020gl088384
Entities
People
- Ren‐Chieh Lien
- Suyang Pei
- Toshiaki Shinoda
- Wanqiu Wang
Organizations
- Division of Ocean Sciences
- National Aeronautics and Space Administration
- National Oceanic and Atmospheric Administration
- United States Department of Defense
- University of Washington