Editorial Type:
Article
Article Type:
Research Article

A New Sea Surface Height–Based Code for Oceanic Mesoscale Eddy Tracking

Evan Mason Instituto Mediterráneo de Estudios Avanzados, Consejo Superior de Investigaciones Científicas, University of the Balearic Islands, Esporles, Illes Balears, Spain

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Ananda Pascual Instituto Mediterráneo de Estudios Avanzados, Consejo Superior de Investigaciones Científicas, University of the Balearic Islands, Esporles, Illes Balears, Spain

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James C. McWilliams Institute of Geophysics and Planetary Physics, University of California, Los Angeles, Los Angeles, California

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Print Publication:
01 May 2014
DOI:
https://doi.org/10.1175/JTECH-D-14-00019.1
Page(s):
1181–1188
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Abstract

This paper presents a software tool that enables the identification and automated tracking of oceanic eddies observed with satellite altimetry in user-specified regions throughout the global ocean. As input, the code requires sequential maps of sea level anomalies such as those provided by Archiving, Validation, and Interpretation of Satellite Oceanographic (AVISO) data. Outputs take the form of (i) data files containing eddy properties, including position, radius, amplitude, and azimuthal (geostrophic) speed; and (ii) sequential image maps showing sea surface height maps with active eddy centers and tracks overlaid. The results given are from a demonstration in the Canary Basin region of the northeast Atlantic and are comparable with a published global eddy track database. Some discrepancies between the two datasets include eddy radius magnitude, and the distributions of eddy births and deaths. The discrepancies may be related to differences in the eddy identification methods, and also possibly to differences in the smoothing of the sea surface height maps. The code is written in Python and is made freely available under a GNU license (http://www.imedea.uib.es/users/emason/py-eddy-tracker/).

Corresponding author address: E. Mason, IMEDEA, CSIC–UIB, C./Miquel Marquès 21, Esporles 07190, Islas Baleares, Spain. E-mail: emason@imedea.uib-csic.es

Abstract

This paper presents a software tool that enables the identification and automated tracking of oceanic eddies observed with satellite altimetry in user-specified regions throughout the global ocean. As input, the code requires sequential maps of sea level anomalies such as those provided by Archiving, Validation, and Interpretation of Satellite Oceanographic (AVISO) data. Outputs take the form of (i) data files containing eddy properties, including position, radius, amplitude, and azimuthal (geostrophic) speed; and (ii) sequential image maps showing sea surface height maps with active eddy centers and tracks overlaid. The results given are from a demonstration in the Canary Basin region of the northeast Atlantic and are comparable with a published global eddy track database. Some discrepancies between the two datasets include eddy radius magnitude, and the distributions of eddy births and deaths. The discrepancies may be related to differences in the eddy identification methods, and also possibly to differences in the smoothing of the sea surface height maps. The code is written in Python and is made freely available under a GNU license (http://www.imedea.uib.es/users/emason/py-eddy-tracker/).

Corresponding author address: E. Mason, IMEDEA, CSIC–UIB, C./Miquel Marquès 21, Esporles 07190, Islas Baleares, Spain. E-mail: emason@imedea.uib-csic.es
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Journal of Atmospheric and Oceanic Technology

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