Coronavirus Information for the UC San Diego Community

Our leaders are working closely with federal and state officials to ensure your ongoing safety at the university. Stay up to date with the latest developments. Learn more.

Turbulence and vorticity in the wake of Palau

TitleTurbulence and vorticity in the wake of Palau
Publication TypeJournal Article
Year of Publication2019
AuthorsSt Laurent L., Ijichi T., Merrifield S.T, Shapiro J., Simmons H.L
Date Published2019/12
Type of ArticleArticle
ISBN Number1042-8275
Accession NumberWOS:000503495700013
Keywordsdissipation; mixed-layer instabilities; ocean; oceanography; slocum

The inleraclion of flow with sleep island and ridge topography at the Palau island chain leads to rich vorticity fields that generate a cascade of motions. The energy transfer to small scales removes energy from the large-scale mean flow of the equatorial current systems and feeds energy to the fine and microstructure scales where instability mechanisms lead to turbulence and dissipation. Until now, direct assessments of the turbulence associated with island wakes have received only minimal attention. Here, we examine data collected from an ocean glider equipped with microstructure sensors that flew in the island wake of Palau. We use a combination of sub-mesoscale modeling and direct observation to quantify the relationship between vorticity and turbulence levels. We find that direct wind-driven mixing only accounts for about 10% of the observed turbulence levels, suggesting that most of the energy for mixing is extracted from the shear associated with the vorticity field in the island's wake. Below the surface layer, enhanced turbulence correlates with the phase and magnitude of the relative vorticity and strain levels of the mesoscale flow.

Student Publication: