气候变化领域集成服务门户(CCPortal): Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability

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DOI	10.1029/2019JC015227
	Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability
	Kerry C.; Roughan M.
发表日期	2020
ISSN	21699275
卷号	125 期号:5
英文摘要	The East Australian Current (EAC) varies on both seasonal and mesoscale eddy related timescales, with important impacts for weather, primary productivity, and fisheries. While the EAC and its eddies have been the subject of many synoptic studies, a consistent three-dimensional picture of the current, its downstream evolution, and the associated seasonal and intra-annual variability is lacking. We use a 22-year model simulation to quantify the EAC's temporal and latitudinal variability, from where it flows as a mostly coherent jet (27° S) to its separation from the coast (31–33° S), its energetic eddy field in the Tasman Sea and its southern extension. We show that the current intensifies and deepens poleward toward the separation latitude; the mean poleward transport reaches a maximum of 26.8 Sv and the seasonal cycle amplitude peaks at 6.2 Sv. Over the separation region, the EAC core broadens and shallows, mean poleward transport is lower and the transport standard deviation peaks at 22.0 Sv. The meandering EAC jet is modulated at interannual timescales, while the eddy driven transport over the separation region has a strong annual modulation, related to the annual cycle in eddy kinetic energy. SSH variability at intra-annual frequencies is described primarily by an alongshore propagating mode and an onshore propagating mode, demonstrating that mesoscale SSH variability stems from a combination of intrinsic instabilities of the EAC jet and westward propagating Rossby waves. The results provide the first holistic analysis of the EAC system along its latitudinal range. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Current transport; East Australian Current; Mesoscale Variability; ROMS; Seasonality; Western Boundary Currents
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/186901
作者单位	Coastal and Regional Oceanography Lab, School of Mathematics and Statistics, UNSW Australia, Sydney, NSW, Australia
推荐引用方式 GB/T 7714	Kerry C.,Roughan M.. Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability[J],2020,125(5).
APA	Kerry C.,&Roughan M..(2020).Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability.Journal of Geophysical Research: Oceans,125(5).
MLA	Kerry C.,et al."Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability".Journal of Geophysical Research: Oceans 125.5(2020).