Wavelets Analysis for Time-tracking Eddies in Regional modelS

2004-2006

PROJECT GOALS
* identifying mesoscale eddies with an objective method,
* time-tracking these eddies and
* evaluating their properties and the water mass they transfer.

Starting from the Wavelab library and ROMS tools we developed a set of MATLAB tools to analyze off-line the modeled circulation in the Cape Basin. In order to identify coherent eddy structures, horizontal slices of the vorticity field at successive time steps are decomposed with a wavelet technique, following a classical approach in image processing.
With the ARIANE toolkit we study eddy displacements and we investigate the water masses involved in eddy formation.
More in scientific works and ...
- Doglioli, A. M., Speich, S., Blanke, B., Lapeyre, G., Tracking Mesoscale Eddies within a Regional Model of the Cape Basin. Ocean Sciences 2006 meeting. Honolulu, Hawaii. abstract slides+notes
- Blanke, B., Doglioli, A. M., Speich, S., Lapeyre, G., Eddy tracking in a regional model of the Cape Basin, Workshop on Indices of Meso-scale Structures. Nantes, France. abstract
- Doglioli, A. M., Blanke, B., Speich, S., Lapeyre, G. (2005), Tracking eddies in a regional model of the Cape Basin off South Africa. J. Geophys. Res., Submitted. see preprint
- Doglioli et al. (2005), Suivi de tourbillons dans un modèle régional du Bassin du Cap (Afrique australe), Atelier InterUp, Brest, 14-16 Novembre. see slides PPT with movies 31.9Mb, PDF
Examples

Bay of Biscay, NORTH ATLANTIC
2D eddy time-tracking and relative vorticity field at 200-m depth
click on the picture to see animated GIF
 3D eddy time-tracking
click on the picture to see animated GIF
Time series of Flierl's depth [m] and transport with associated uncertainty [Sv]
 Time series of eddy velocity [m/s], volume [m³] and diameter [m]

Cape Basin, SOUTH ATLANTIC
Cyclone Panoramix
2D eddy time-tracking and relative vorticity field at 200-m depth
click on the picture to see animated GIF
 3D eddy time-tracking
click on the picture to see animated GIF
Anticyclone Idefix
2D eddy time-tracking and relative vorticity field at 200-m depth
click on the picture to see animated GIF
 3D eddy time-tracking
click on the picture to see animated GIF

TO DOWNLOAD THE WATERS User Guide (draft version)
CLICK HERE .

TO DOWNLOAD THE WATERS MATLAB PACKAGE
-the "prehistoric" version!-,
CLICK HERE .

TO SEE THE LIST OF THE prehistoric-WATERS' DOWNLOADERS,
CLICK HERE [HTML] .

Related Works

Contreras Contreras, M.P., 2014. Dinámica Océanica de Mesoescala frente a Chile Central Detección de Remolinos por algoritmo WATERS Tópico en Geofísica II. see slides

Souza, J. M. A. C., de Boyer Montégut, C., and Le Traon, P. Y., 2011. Comparison between three implementations of automatic identification algorithms for the quantification and characterization of mesoscale eddies in the South Atlantic Ocean, Ocean Sci., 7, 317-334, doi: 10.5194/os-7-317-2011.

Dencausse, G., Arhan, M., Speich, S. 2010. Routes of Agulhas rings in the southeastern Cape Basin, Deep Sea Res., 57, 11, 1406-1421, doi: 10.1016/j.dsr.2010.07.008.

Rubio, A., Blanke, B., Speich, S., Grima, N., Roy, C., 2009. Mesoscale eddy activity in the southern Benguela upwelling system from satellite altimetry and model data, Progr.Oceanogr., 83, 1-4, 288-295, doi:10.1016/j.pocean.2009.07.029.

Doglioli, A.M., Blanke, B., Speich, S., Lapeyre, G., 2007. Tracking coherent structures in a regional ocean model with wavelet analysis: application to Cape Basin Eddies. J. Geophys. Res., 112, C05043, doi:10.1029/2006JC003952.


2009, a new project !
WASSCO
Waters - Application de Suivi de Structures COhérentes 3D
dans des modèles de circulation océanique haute résolution MERCATOR
et comparaison avec des données altimétriques)
PI: N. Grima (LPO, Brest)
[website]

http://www.mio.univ-amu.fr/~doglioli