Coherence between Stratification and Shear in the Upper Ocean.
Abstract
A number of mechanisms are known to be responsible for the interdependence of stratification and shear. These include interleaving, internal waves, and instabilities such as double diffusion and breaking internal waves. In the strongly stratified seasonal thermocline the shear behaves approximately as S2 is directly proportional to N2 (Grabowski, 1980). Patterson et. al. (1981) showed that N2 and S2 are better correlated over vertical scales of 30 meters or more. This calculation of cross coherence between simultaneous profiles of N2 and S2 was intended to investigate the possibility of a limiting vertical length scale below which the correlation of N2 and S2 is small or zero, and above which the correlation is good. On the basis of a limited data set (9 YVETTE profiles), N2 and S2 appear in general to be well correlated at wavelengths larger than about 5-10 meters, except in the presence of large vertical geostrophic shear. These results offer some further evidence that levels of shear activity may be inferred from stratification at scales down to about 10 meters. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1982
- Accession Number
- ADA120998
Entities
People
- David M. Rubenstein
- Fred C. Newman
- Richard Lambert Jr