Abstract
Seven-year (2005–2011) Synthetic Aperture Radar (SAR) images are applied to study oceanic eddies in the East China Sea. It is found that most of these eddies detected from the SAR images are less than 10 km, which are submesoscale eddies. Seasonal differences are evident in the distribution of eddies, with the highest and the lowest number of eddies noted in summer and winter, respectively. Since slick streaks in SAR images look dark, an eddy identified due to the slicks is referred to as “black eddy”. As a result of wave-current interactions in the zones of current shear, it can be seen that an eddy exhibits a bright curve, the eddy is called “white eddy”. During the seven years, 95 black eddies and 50 white eddies are identified in the study area. Black eddies are found in the whole study area while white eddies are mainly distributed in the vicinity of the Kuroshio Current. This study suggests that the distribution of the white eddy is denser around the Kuroshio because of the strong shear in the Kuroshio region. In terms of the eddy sizes, white eddies are generally smaller than black eddies.
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The National Key Research and Development Program of China under contract Nos 2016YFA0601803 and 2017YFA0604100; the National Natural Science Foundation of China under contract Nos 41476022, 41490643 and 41706008; the China Ocean Mineral Resources R&D Association under contract Nos DY135-E2-2-02 and DY135-E2-3-01.
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Ji, Y., Xu, G., Dong, C. et al. Submesoscale eddies in the East China Sea detected from SAR images. Acta Oceanol. Sin. 40, 18–26 (2021). https://doi.org/10.1007/s13131-021-1714-5
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DOI: https://doi.org/10.1007/s13131-021-1714-5