Coherent Lagrangian Pathways Near an East Alboran Front

Abstract

In the eastern Alboran Sea, frontogenesis (FG) is a dominant process for fronts extending from the Spanish coast toward the basin interior, promoting large vertical displacements that connect the surface mixed layer with the oceanic interior. Using a realistic, high‐resolution model simulation for this region, we conduct the offline advection of virtual water parcels released near the surface during a 2‐day episode of intense FG. Three‐dimensional trajectories exhibit high variability depending on the release location, and some large, rapid vertical displacements are induced by different coherent submesoscale flow patterns and by interactions among them: Ageostrophic secondary circulation associated with strain‐ and mixing‐induced FG and internal waves generated by currents over topography. These deep displacements mostly are irreversible, at least on a short time scale, because of the rapidly changing flow patterns. Significant diapycnal mixing and density changes occur along trajectories as they pass through the surface and bottom boundary layers. While we expect these processes to be typical for this region, the computational expense of such a Lagrangian analysis and the complexity of its outcome present a considerable challenge for more comprehensive assessments.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 25, 2022
Source ID
10.1029/2021jc018022

Entities

People

  • Esther Capó
  • James C. McWilliams

Organizations

  • Office of Naval Research

Tags

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers