气候变化领域集成服务门户(CCPortal): Submesoscale Eddy and Frontal Instabilities in the Kuroshio Interacting With a Cape South of Taiwan

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DOI	10.1029/2020JC016123
	Submesoscale Eddy and Frontal Instabilities in the Kuroshio Interacting With a Cape South of Taiwan
	Cheng Y.-H.; Chang M.-H.; Ko D.S.; Jan S.; Andres M.; Kirincich A.; Yang Y.J.; Tai J.-H.
发表日期	2020
ISSN	21699275
卷号	125 期号:5
英文摘要	The processes underlying the strong Kuroshio encountering a cape at the southernmost tip of Taiwan are examined with satellite-derived chlorophyll and temperature maps, a drifter trajectory, and realistic model simulations. The interaction spurs the formation of submesoscale cyclonic eddies that trap cold and high-chlorophyll water and the formation of frontal waves between the free stream and the wake flow. An observed train of eddies, which have relative vorticity about one to four times the planetary vorticity (f), is shed from the recirculation that occurs in the immediate lee of the cape as a result of flow separation. These propagate downstream at a speed of 0.5–0.6 m s−1. Farther downstream, the corotation and merging of two or three adjacent eddies are common owing to the topography-induced slowdown of eddy propagation farther downstream. It is found that the relative vorticity of a corotating system (1.2f) is 70% weaker than that of a single eddy due to the increase of eddy diameter from ~16 to ~33 km, in agreement with Kelvin's circulation theorem. The shedding period of the submesoscale eddies is strongly modulated by either diurnal or semidiurnal tidal flows, which typically reach 0.2–0.5 m s−1, whereas its intrinsic shedding period is insignificant. The frontal waves predominate in the horizontal free shear layer emitted from the cape, as well as a density front. Energetics analysis suggests that the wavy features result primarily from the growth of barotropic instability in the free shear layer, which may play a secondary process in the headland wake. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	barotropic instability; eddy corotation; headland; Kuroshio; recirculation; submesoscale eddy
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186898
作者单位	Institute of Oceanography, National Taiwan University, Taipei, Taiwan; Oceanography Division, Naval Research Laboratory, Stennis Space CenterMS, United States; Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, MA, United States; Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
推荐引用方式 GB/T 7714	Cheng Y.-H.,Chang M.-H.,Ko D.S.,et al. Submesoscale Eddy and Frontal Instabilities in the Kuroshio Interacting With a Cape South of Taiwan[J],2020,125(5).
APA	Cheng Y.-H..,Chang M.-H..,Ko D.S..,Jan S..,Andres M..,...&Tai J.-H..(2020).Submesoscale Eddy and Frontal Instabilities in the Kuroshio Interacting With a Cape South of Taiwan.Journal of Geophysical Research: Oceans,125(5).
MLA	Cheng Y.-H.,et al."Submesoscale Eddy and Frontal Instabilities in the Kuroshio Interacting With a Cape South of Taiwan".Journal of Geophysical Research: Oceans 125.5(2020).