气候变化领域集成服务门户(CCPortal): The Multi-Scale Response of the Eddy Kinetic Energy and Transport to Strengthened Westerlies in an Idealized Antarctic Circumpolar Current

CCPortal

DOI	10.1029/2023GL106747
	The Multi-Scale Response of the Eddy Kinetic Energy and Transport to Strengthened Westerlies in an Idealized Antarctic Circumpolar Current
	Liu, Ran; Wang, Guihua; Balwada, Dhruv
发表日期	2024
ISSN	0094-8276
EISSN	1944-8007
起始页码	51
结束页码	8
卷号	51 期号:8
英文摘要	The Southern Ocean's eddy response to changing climate remains unclear, with observations suggesting non-monotonic changes in eddy kinetic energy (EKE) across scales. Here simulations reappear that smaller-mesoscale EKE is suppressed while larger-mesoscale EKE increases with strengthened winds. This change was linked to scale-wise changes in the kinetic energy cycle, where a sensitive balance between the dominant mesoscale energy sinks-inverse KE cascade, and source-baroclinic energization. Such balance induced a strong (weak) mesoscale suppression in the flat (ridge) channel. Mechanistically, this mesoscale suppression is attributed to stronger zonal jets weakening smaller mesoscale eddies and promoting larger-scale waves. These EKE multiscale changes lead to multiscale changes in meridional and vertical eddy transport, which can be parameterized using a scale-dependent diffusivity linked to the EKE spectrum. This multiscale eddy response may have significant implications for understanding and modeling the Southern Ocean eddy activity and transport under a changing climate. The response of eddies in the Southern Ocean to climate change is not well understood. In this study, we used a channel model that simulates the effects of wind on eddies. We found that smaller eddies have less kinetic energy (KE) when the winds are stronger. On the other hand, larger-scale eddies have more KE with stronger winds. Similar phenomena are also observed in the observations. By analyzing the eddy's KE budget, the interaction between different scales of eddies and the interaction between the eddies and mean flow are strengthened when the winds get stronger. This leads to a reduction of eddy KE at smaller mesoscale scales and an increase at larger scales. From the observational view, stronger winds weaken smaller eddies and promote larger waves. This change in eddy KE also affects how eddies meridionally transport materials and how eddy diffusivity varies at different scales. Smaller eddies transport materials less when their KE is weakened, while larger eddies become stronger in transporting materials. These findings determine how eddy diffusivity responds to the changed eddy KE at different scales. The multi-scale response of eddies to wind has important implications for understanding the behavior of Southern Ocean eddies in a changing climate. Larger eddies got stronger and smaller eddies got weaker as Southern Ocean westerlies strengthened Both flat and ridge channel simulations suggest that these changes may be linked to changes in the inverse energy cascade The corresponding changes in scale-wise meridional and vertical transport are also non-monotonic
英文关键词	Southern Ocean; mesoscale eddy; multiscale dynamics; eddy kinetic energy spectrum
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:001205265100001
来源期刊	GEOPHYSICAL RESEARCH LETTERS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/306370
作者单位	Fudan University; Fudan University; Hong Kong University of Science & Technology; Columbia University
推荐引用方式 GB/T 7714	Liu, Ran,Wang, Guihua,Balwada, Dhruv. The Multi-Scale Response of the Eddy Kinetic Energy and Transport to Strengthened Westerlies in an Idealized Antarctic Circumpolar Current[J],2024,51(8).
APA	Liu, Ran,Wang, Guihua,&Balwada, Dhruv.(2024).The Multi-Scale Response of the Eddy Kinetic Energy and Transport to Strengthened Westerlies in an Idealized Antarctic Circumpolar Current.GEOPHYSICAL RESEARCH LETTERS,51(8).
MLA	Liu, Ran,et al."The Multi-Scale Response of the Eddy Kinetic Energy and Transport to Strengthened Westerlies in an Idealized Antarctic Circumpolar Current".GEOPHYSICAL RESEARCH LETTERS 51.8(2024).