气候变化领域集成服务门户(CCPortal): Intra- and Inter-Annual Variability of North Brazil Current Rings Using Angular Momentum Eddy Detection and Tracking Algorithm: Observations From 1993 to 2016

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DOI	10.1029/2019JC015921
	Intra- and Inter-Annual Variability of North Brazil Current Rings Using Angular Momentum Eddy Detection and Tracking Algorithm: Observations From 1993 to 2016
	Aroucha L.C.; Veleda D.; Lopes F.S.; Tyaquiçã P.; Lefèvre N.; Araujo M.
发表日期	2020
ISSN	21699275
卷号	125 期号:12
英文摘要	In order to investigate intra- and inter-annual variability of North Brazil Current (NBC) rings, angular momentum eddy detection and tracking algorithm (AMEDA) was used for identification of their occurrence, trajectories, and parameters. Based on 24 years (1993–2016) of geopotential height and geostrophic current fields reanalysis data from ARMOR 3D (¼°), we identified an average rate of five NBC rings shed by year. The rings present an average lifetime of 15.3 (±5.4) weeks, average speed-based radius (Rmax) of 139.8 (±23.6) km, and mean sea surface height anomaly (SSHa) of 9.4 (±4.0) cm. The mean observed maximum azimuthal velocity (Vmax) was 0.27 (±0.08) m/s, while the averaged Rossby number (Ro) value was 0.08 (±0.04) and averaged kinetic energy (KE) was of 255.3 (±154.8) cm2/s2. NBC rings have larger dimensions, rotate faster, live less, and transfer more energy in boreal winter months. In contrast, those shed during boreal summer and early fall last longer, have smaller diameters and carry less energy. Besides, the analysis of ring merging pointed that the interaction between NBC rings generated a significantly increase in ring energy (52%), and velocity (22%). Finally, we observed the vertical anomalies temperature and salinity profiles, which indicated a thermocline deepening and sinking of coastal and tropical waters due to NBC rings downwelling. This study emphasizes the robustness and efficiency of AMEDA for studying rings in the ocean and further theorizes possible impacts of NBC ring on ocean physical and biogeochemical features in the Western Tropical North Atlantic. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	AMEDA algorithm; NBC Rings; Ocean eddies; Tropical Atlantic
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/186575
作者单位	Laboratory of Physical, Coastal and Estuarine Oceanography – LOFEC, Federal University of Pernambuco – UFPE, Recife, Brazil; Renewable Energy Center – CER, Federal University of Pernambuco – UFPE, Recife, Brazil; Now at Department of Oceanography - UFPE, Cidade Universitária, Recife, Brazil; LOCEAN, IRD, Sorbonne Université Paris, Paris, France; Center for Risk Analysis and Environmental Modeling – CEERMA, Federal University of Pernambuco – UFPE, Recife, Brazil
推荐引用方式 GB/T 7714	Aroucha L.C.,Veleda D.,Lopes F.S.,et al. Intra- and Inter-Annual Variability of North Brazil Current Rings Using Angular Momentum Eddy Detection and Tracking Algorithm: Observations From 1993 to 2016[J],2020,125(12).
APA	Aroucha L.C.,Veleda D.,Lopes F.S.,Tyaquiçã P.,Lefèvre N.,&Araujo M..(2020).Intra- and Inter-Annual Variability of North Brazil Current Rings Using Angular Momentum Eddy Detection and Tracking Algorithm: Observations From 1993 to 2016.Journal of Geophysical Research: Oceans,125(12).
MLA	Aroucha L.C.,et al."Intra- and Inter-Annual Variability of North Brazil Current Rings Using Angular Momentum Eddy Detection and Tracking Algorithm: Observations From 1993 to 2016".Journal of Geophysical Research: Oceans 125.12(2020).