气候变化领域集成服务门户(CCPortal): Characteristics and Trends of the Campbell Plateau Meander in the Southern Ocean: 1993-2020

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DOI	10.1029/2023JC019876
	Characteristics and Trends of the Campbell Plateau Meander in the Southern Ocean: 1993-2020
	Liu, Xinlong; Meyer, Amelie; Chapman, Christopher C.
发表日期	2024
ISSN	2169-9275
EISSN	2169-9291
起始页码	129
结束页码	2
卷号	129 期号:2
英文摘要	Meanders are significant features of the Antarctic Circumpolar Current in the Southern Ocean and sites of enhanced upwelling, cross-frontal tracer fluxes, and exchanges between the surface and deep ocean. They often overlap the locations of fronts and are linked to topographic features. While much is known about Southern Ocean fronts and how they are changing, the response of meanders to climate change is largely unexplored. In this study, we investigate the Campbell Plateau meander south of New Zealand. We apply a local gradient maxima method to satellite altimetry data to identify the position of the meander and estimate its width, geostrophic current speed, and associated trends from 1993 to 2020. We find that the position of the meander has been relatively fixed, except for a section downstream of the Plateau, which has shifted northward by about 0.4 degrees latitude per decade. The meander has become flatter at the western edge of the Plateau, but steeper at the eastern edge of the Plateau. Overall, the meander has widened by 2 km per decade and accelerated by 0.01 m s-1 per decade, particularly downstream of the Plateau. These findings are consistent with other work on standing meanders in the Southern Ocean. Increases in eddy kinetic energy and of the South Pacific Gyre index support our hypotheses that changes in the downstream jet stability and the South Pacific Gyre contribute to these observed trends. The impacts of these trends on cross-frontal transport remain to be evaluated. In the Southern Ocean, meanders are parts of the Antarctic Circumpolar Current (ACC) that deviate from the usual west-to-east flow by having a substantial north-south component, resulting in a wave-like appearance. Standing meanders are meanders that are stationary and do not move much over months and years. They are a special feature of the ACC and are fundamental for exchanges between the surface and deep ocean. Although changes in the ACC have been well studied, especially in the context of climate change, very little is known about how Southern Ocean meanders are changing. This study focuses on the Campbell Plateau meander south of New Zealand in the Southern Ocean. Using ocean sea surface height data from satellites, we analyze the monthly position of this meander, estimate its monthly width and speed, and quantify how these characteristics have changed over the 1993-2020 period. Upstream of the Campbell Plateau, the meander has undergone almost no changes in its position, width or speed. However, downstream of the Plateau, the meander has shifted northward, widened and accelerated. These trends are consistent with other observations in the Southern Ocean, and we discuss potential mechanisms to explain them. The position of the Campbell Plateau meander has remained stable for the past 30 years, apart from a section downstream shifting northward The amplitude of the Campbell Plateau meander has been decreasing (flatter) upstream of the Plateau and increasing (steeper) downstream The Campbell Plateau meander has been widening and accelerating over the 1993-2020 period, especially downstream of the Plateau
英文关键词	Southern Ocean; Antarctic Circumpolar Current; fronts and jets; standing meanders; trend; ocean dynamics
语种	英语
WOS研究方向	Oceanography
WOS类目	Oceanography
WOS记录号	WOS:001166353700001
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/296367
作者单位	University of Tasmania; University of Tasmania; University of Tasmania; Commonwealth Scientific & Industrial Research Organisation (CSIRO)
推荐引用方式 GB/T 7714	Liu, Xinlong,Meyer, Amelie,Chapman, Christopher C.. Characteristics and Trends of the Campbell Plateau Meander in the Southern Ocean: 1993-2020[J],2024,129(2).
APA	Liu, Xinlong,Meyer, Amelie,&Chapman, Christopher C..(2024).Characteristics and Trends of the Campbell Plateau Meander in the Southern Ocean: 1993-2020.JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS,129(2).
MLA	Liu, Xinlong,et al."Characteristics and Trends of the Campbell Plateau Meander in the Southern Ocean: 1993-2020".JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 129.2(2024).