• Corpus ID: 244714901

Quasi-Objective Eddy Visualization from Sparse Drifter Data

@inproceedings{Bartos2021QuasiObjectiveEV,
  title={Quasi-Objective Eddy Visualization from Sparse Drifter Data},
  author={Alex P. Encinas Bartos and Nikolas O.Aksamit and George Haller},
  year={2021}
}

• A. Bartos, Nikolas O.Aksamit, G. Haller
• Published 28 November 2021
• Environmental Science, Physics

We employ a recently developed single-trajectory Lagrangian diagnostic tool, the trajectory rotation average (TRA) , to visualize oceanic vortices (or eddies) from sparse drifter data. We apply the TRA to two drifter data sets that cover various oceanographic scales: the Grand Lagrangian Deployment (GLAD) and the Global Drifter Program (GDP). Based on the TRA , we develop a general algorithm that extracts approximate eddy boundaries. We find that the TRA outperforms other available single-trajectory-based eddy detection methodologies on sparse drifter data and identifies eddies on scales that are unresolved by satellite-altimetry. closely approximate appropriate objective LCS diagnostics in frames satisfying conditions that typically hold in geophysical flows. We show that the adiabatically quasi-objective trajectory rotation average ( TRA ) reveals elliptic LCSs (material eddies) at meso-and submesoscales from sparse drifter trajectory data. We additionally compare the vortical flow features extracted from the drifter-based TRA computation with those obtained from other available Lagrangian single-trajectory diagnostics such as the trajectory length [38, 37] and the Lagrangian spin [55, 32]. We further validate the extracted features with respect to Lagrangian averaged vorticity deviation (LAVD) [26] computed from geostrophic ocean velocity fields derived from