Research on the variability of Brazil-Malvinas Confluence and its cause

Fan Xiumei; Fan Wei; Tang Fenghua; Wu Zuli

doi:10.3969/j.issn.0253-4193.2019.09.008

Volume 41 Issue 9

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Fan Xiumei，Fan Wei，Tang Fenghua, et al. Research on the variability of Brazil-Malvinas Confluence and its cause[J]. Haiyang Xuebao，2019, 41(9)：86–93，doi:10.3969/j.issn.0253−4193.2019.09.008

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Research on the variability of Brazil-Malvinas Confluence and its cause

doi: 10.3969/j.issn.0253-4193.2019.09.008

Fan Xiumei^{1, 2
,},
Fan Wei^{1, 2},
Tang Fenghua^{1, 2},
Wu Zuli^{1, 2}

1.
Key and Open Laboratory of Fisheries Resources Remote Sensing and Information Technology, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China
2.
Key Laboratory of Development and Utilization of East China Sea and Ocean Fisheries Resources, Ministry of Agriculture, Shanghai 200090, China

Received Date: 2018-08-27
Rev Recd Date: 2019-02-16

Available Online: 2021-04-21

Publish Date: 2019-09-25

Abstract

Abstract

The Brazil-Malvinas Confluence (BMC) may have a southward shift in a long time trend and many marine factors’ change may cause this drift. We analysis this phenomenon from two aspects: the changes of currents’ volume transport, and the winds’ alternation. Using the monthly mean flow field between 1993 and 2016 to calculate the cross-sectional water transport volume, the results show that the transport change trend of the Malvinas Current (MC) is decreasing and the transport change trend of the Brazil Current (BC) is increasing. The trajectory of the Argo buoy during 2014–2016 indicates that the MC’s water mainly comes from one of the three polar fronts of ACC (Antarctic Circumpolar Current) when passing through the Drake Passage: SAF (the Subantactic Front). Calculating and analyzing the transport of SAF, we find that the transport’s trend of SAF is lessened, which is an important reason caused the reduce of MC’s transport. We also find that the PF’s transport on the south SAF has incremental trend. Based on the monthly mean wind field data during year 1993–2016, we find that the prevailing westerly wind stress in the Southern Hemisphere is growing and moves toward to Antarctic which will make ACC contract to Antarctica. So we can explain that the transport of SAF reduces while the transport of PF increases. Therefore, it is found that the southward movement of the prevailing westerly winds in the Southern Hemisphere and the increase of BC transport are the reasons for the southward drift of BMC.
- wind stress,
- confluence,
- transport,
- Argo

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References(12)

References

[1]	陈新军, 赵小虎. 西南大西洋阿根廷滑柔鱼产量分布与表温关系的初步研究[J]. 大连水产学报, 2005, 20(3): 222−228. Chen Xinjun, Zhao Xiaohu. The relationship between the distribution of production of squid Illex argentinus and sea surface temperature in the Southwest Atlantic Ocean[J]. Journal of Dalian Fisheries University, 2005, 20(3): 222−228.
[2]	Friocourt Y, Drijfhout S, Blanke B, et al. Water mass export from drake passage to the Atlantic, Indian, and Pacific oceans: a Lagrangian model analysis[J]. Journal of Physical Oceanography, 2005, 35(7): 1206−1222. doi: 10.1175/JPO2748.1
[3]	Goni G, Kamholz S, Garzoli S, et al. Dynamics of the Brazil-Malvinas confluence based on inverted echo sounders and altimetry[J]. Journal of Geophysical Research, 1996, 101(C7): 16273−16289. doi: 10.1029/96JC01146
[4]	Goni G J, Bringas F, DiNezio P N. Observed low frequency variability of the Brazil Current front[J]. Journal of Geophysical Research, 2011, 116(C10): C10037. doi: 10.1029/2011JC007198
[5]	Combes V, Matano P R. Trends in the Brazil/Malvinas confluence region[J]. Geophysical Research Letters, 2014, 41(24): 8971−8977. doi: 10.1002/2014GL062523
[6]	Garzoli S L, Baringer M O. Meridional heat transport determined with expandable bathythermographs—Part II: south Atlantic transport[J]. Deep Sea Research Part I: Oceanographic Research Papers, 2007, 54(8): 1402−1420. doi: 10.1016/j.dsr.2007.04.013
[7]	Vivier F, Provost C. Volume transport of the Malvinas Current: can the flow be monitored by TOPEX/POSEIDON?[J]. Journal of Geophysical Research, 1999, 104(C9): 21105−21122. doi: 10.1029/1999JC900056
[8]	Matano R P. On the separation of the Brazil Current from the coast[J]. Journal of Physical Oceanography, 1993, 23(1): 79−90. doi: 10.1175/1520-0485(1993)023<0079:OTSOTB>2.0.CO;2
[9]	Piola A R, Franco B C, Palma E D, et al. Multiple jets in the Malvinas Current[J]. Journal of Geophysical Research, 2013, 118(4): 2107−2117.
[10]	Orsi A H, Whitworth T, Nowlin Jr D W. On the meridional extent and fronts of the Antarctic circumpolar current[J]. Deep Sea Research Part I: Oceanographic Research Papers, 1995, 42(5): 641−673. doi: 10.1016/0967-0637(95)00021-W
[11]	郭吉鸽, 谢基平, 朱江. 利用Argo浮标轨迹推断大洋表层和中层海流[G]//Argo应用研究论文集. 北京: 海洋出版社, 2006. Guo Jige, Xie Jiping, Zhu Jiang. Estimation of the surface and mid-depth currents from Argo floats[G]//Argo Science Seminar in China. Beijing: China Ocean Press, 2006.
[12]	Carton J A, Giese B S. A reanalysis of ocean climate using simple ocean data assimilation (SODA)[J]. Monthly Weather Review, 2008, 136(8): 2999−3017. doi: 10.1175/2007MWR1978.1