ESC seminar No. 39

Simulations of stratified turbulence surrounding Meddy structures

Date
June 26 (Thu.), 2008, 16:00-17:00
Place
Conference Room, 5F, Information Technology Building, YES
Speaker
Dr.Lien Hua (IFREMER, Laboratoire de Physique des Oceans, Brest)
Language
English

Abstract

Recently available geosismic data in the North-East Atlantic ocean have revealed ubiquituous "pancake"-like layers of temperature anomaly of 30-60 meters thickness, surrounding the abundant Meddy structures within the Mediterranean Water outflow. The depths of pancake-like layering unambiguously coincide with potential energy spectra in kh-5/3,-- where kh is the horizontal wavenumber--, reminiscent of non-rotating stratified turbulence results.

Using high resolution simulations of a Meddy structure, with a horizontal grid size down to 100m and a vertical grid size of 3m, we have been able to reproduce the pancake-like layering surrounding the eddy. Moreover potential and kinetic energy with kh-5/3 inertial ranges have been simulated. A rationaleis proposed for the formation mechanism of the layering and we discuss the influence of rotation onstratifed turbulence properties.

Contact

Wataru Ohfuchi
Earth Simulator Center
TEL: 045-778-5765
FAX: 045-778-5492
e-mail: ohfuchi