Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46579 10.2205/2021ES000764 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Three-Dimensional Structure of the mesoscale eddies in the Agulhas Current region from hydrological and altimetry data Three-Dimensional Structure of the mesoscale eddies in the Agulhas Current region from hydrological and altimetry data Sandalyuk N V Sandalyuk N V n.sandalyuk@spbu.ru Belonenko T V Belonenko T V Saint Petersburg State University ru Saint Petersburg State University ru Saint Petersburg State University ru Saint Petersburg State University ru 21 4 29 10 2021 https://rjes.ru/en/nauka/article/46579/view

In this work by implementing the method of colocalization the altimetry data and temperature and salinity profiles we provide a detailed study of the averaged thermohaline structure of the anticyclonic and cyclonic mesoscale eddies formed in the southern part of the Agulhas Current system. The observed intensification of eddy dissipation processes can be caused by the topographic barriers, such as the Agulhas Plateau or the Agulhas Ridge. In the eddies of both polarities significant temperature anomalies are concentrated within the distance of one radius from the eddy center and to the depth of ∼ 1500 m. The obtained averaged estimates of heat and salt transported by the Agulhas Rings is 2.38 × 1020 J and 4.79 × 1012 kg respectively. Westward propagation of the zonal eddy-induced transport for anticyclonic and cyclonic eddies is observed in the Agulhas Retroflection region, Cape Basin and in the central part of the shelf zone with the maximum values of 4 Sv/deg2 for anticyclonic eddies and 1.77 Sv/deg2 for cyclonic eddies.

In this work by implementing the method of colocalization the altimetry data and temperature and salinity profiles we provide a detailed study of the averaged thermohaline structure of the anticyclonic and cyclonic mesoscale eddies formed in the southern part of the Agulhas Current system. The observed intensification of eddy dissipation processes can be caused by the topographic barriers, such as the Agulhas Plateau or the Agulhas Ridge. In the eddies of both polarities significant temperature anomalies are concentrated within the distance of one radius from the eddy center and to the depth of ∼ 1500 m. The obtained averaged estimates of heat and salt transported by the Agulhas Rings is 2.38 × 1020 J and 4.79 × 1012 kg respectively. Westward propagation of the zonal eddy-induced transport for anticyclonic and cyclonic eddies is observed in the Agulhas Retroflection region, Cape Basin and in the central part of the shelf zone with the maximum values of 4 Sv/deg2 for anticyclonic eddies and 1.77 Sv/deg2 for cyclonic eddies.

 Agulhas Rings Agulhas Current mesoscale eddies altimetry Agulhas Rings Agulhas Current mesoscale eddies altimetry This research was supported by the by the Russian Foundation for Basic Research (project No. 20-05-00066). The publication was funded by Saint Petersburg State University, project N 75295423.

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