Characteristics of Oceanic Eddies in the North Pacific
Abstract
In this study, oceanic eddies in the north Pacific derived from satellite altimetry are statistically analyzed. An integration filtering algorithm based on connected component labeling and the Okubo-Weiss parameter is developed. The originated area, translation speed, and propagation pathway of all identified eddies are all determined by the integration filtering algorithm. Only eddies that have longer life span more than 12 weeks are considered. The results indicate that there are quantities of eddies with tens to hundreds of kilometers in spatial scales, and tens to hundreds of days in temporal scales. The 83% of eddies are generated between 15 degree North and 40 degree North and average translation speed is 4.5±1.9 km/day. The average life span is 20±11weeks, but warm eddies have longer life span than cold eddies. There are about 300 eddies generated in this ocean per year, but numbers of eddy keeps gaining more and more with a trend of 1.7±0.4 numbers per year. More interesting thing is that cold eddies with a trend of 1.1±0.5 numbers per year are growing more than warm eddies with a trend of 0.6±0.4 numbers per year. Referring to the pathway, most eddies propagate westward with slightly equatorward and poleward deflection of cold and warm eddies, respectively in the western North Pacific but not in the eastern North Pacific.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMOS21D1776H
- Keywords:
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- 4275 OCEANOGRAPHY: GENERAL / Remote sensing and electromagnetic processes;
- 4520 OCEANOGRAPHY: PHYSICAL / Eddies and mesoscale processes