Generation of cold anticyclonic eddies and warm cyclonic eddies in the tropical oceans

Ni, Qinbiao, Zhai, Xiaoming, Yang, Zhibin and Chen, Dake (2023) Generation of cold anticyclonic eddies and warm cyclonic eddies in the tropical oceans. Journal of Physical Oceanography, 53 (6). 1485–1498. ISSN 0022-3670

Preview

PDF (JPO_D_22_0197_R1) - Accepted Version Available under License Creative Commons Attribution. Download (2MB) | Preview

Abstract

Mesoscale eddies are ubiquitous features of the global ocean circulation. Traditionally, anticyclonic eddies are thought to be associated with positive temperature anomalies while cyclonic eddies are associated with negative temperature anomalies. However, our recent study found that about one-fifth of the eddies identified from global satellite observations are cold-core anticyclonic eddies (CAEs) and warm-core cyclonic eddies (WCEs). Here we show that in the tropical oceans where the probabilities of CAEs and WCEs are high, there are significantly more CAEs and WCEs in summer than in winter. We conduct a suite of idealized numerical model experiments initialized with composite eddy structures obtained from Argo profiles as well as a heat budget analysis. The results highlight the key role of relative wind-stress-induced Ekman pumping, surface mixed layer depth, and vertical entrainment in the formation and seasonal cycle of these unconventional eddies. The relative wind stress is found to be particularly effective in converting conventional eddies into CAEs or WCEs when the surface mixed layer is shallow. The abundance of CAEs and WCEs in the global ocean calls for further research on this topic.

Item Type:	Article
Additional Information:	Data availability statement: All the observational data used in this study are publicly available. The altimeter SLA data are available at http://marine.copernicus.eu/. The microwave SST data are available at http://www.remss.com/. The QuikSCAT wind speed data are available at https://cersat.ifremer.fr/. The Argo profile data are available at http://www.argo.org.cn/. Acknowledgments: Q. Ni is supported by the National Natural Science Foundation of China (42106011) and an International Postdoctoral Exchange Fellowship awarded by the Office of China Postdoctoral Council. Z. Yang is supported by National Natural Science Foundation of China (41776006, 41822601) and Taishan Scholar Funds (tsqn201909052). D. Chen is supported by the National Natural Science Foundation of China (42227901).
Faculty \ School:	Faculty of Science > School of Environmental Sciences Faculty of Science > School of Natural Sciences
UEA Research Groups:	Faculty of Science > Research Groups > Centre for Ocean and Atmospheric Sciences
Depositing User:	LivePure Connector
Date Deposited:	13 Mar 2023 12:30
Last Modified:	15 Jun 2023 11:32
URI:	https://ueaeprints.uea.ac.uk/id/eprint/91492
DOI:	10.1175/JPO-D-22-0197.1

Downloads

Actions (login required)

View Item