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Temporal and spatial evolution of a deep-reaching anticyclonic eddy in the South China Sea

  • Meng Wang
  • Yanwei ZhangEmail author
  • Zhifei Liu
  • Yulong Zhao
  • Jianru Li
Research Paper
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Abstract

The temporal and spatial evolution of a deep-reaching anticyclonic eddy (AE) is studied using a combination of satellite measurements, moored observations and ocean model reanalysis data in the South China Sea (SCS). Three evolutionary stages in eddy’s lifecycle are identified from changes in eddy dynamical characteristics estimated from satellite altimetry: birth (22 days), growth (64 days), and decay (47 days). Similar patterns are also distinguished from dynamic signals in HYCOM. Further, flows reversal and upwelling of cold water below 1500 m were captured by the in-situ records when this energetic, highly nonlinear and long-lived (over 19 weeks) AE passed by our mooring position. Its detailed vertical structure is examined through temperature anomalies, vertical shear of horizontal velocities, and horizontal streamlines estimated from ocean model reanalysis data. Results from the model reveal a mesoscale AE with first-mode baroclinic structure: a bowl-shaped anticyclonic flow in the upper ocean connected to a slant-cylinder cyclonic flow at depth, with a transition layer at depths between 400 and 700 m. It is in good agreement with moored observations but showing a shallower transition depth, suggesting a slight deficiency in the model due to limited deep-sea observations. Last, we estimate eddy heat transport at different depths and stages along the AE’s path based on the model data. The result reveals that pronounced heat fluxes occur during growth stage (depths <400 m), counting for 73.03% of the total value. In the decay stage, major heat transport occurs at deeper depth (depths >700–1500 m). Dynamical characteristics suggest that the vertical structure and temporal evolution of the eddy play significant roles in basin-scale movement and heat transferring. Considering that mesoscale eddies are ubiquitous in the SCS, our results support a recently-proposed mechanism, whereby upper ocean flows produce changes in the deep-sea circulation, potentially influencing boundary layer dynamics. For the first time to track and link an individual AE observed by satellite altimetry and ocean model, comparisons indicate that assimilative HYCOM outputs may be useful for examining the deep ocean properties within the SCS, especially under the impact of such an intensified surface-detected eddy.

Keywords

Deep-reaching mesoscale eddy Evolution HYCOM The South China Sea 

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Notes

Acknowledgements

We thank Shaohua Zhao, Xiajing Li, Quan Chen, Qin Zhang, Yanli Li, and Ke Wen for their assistance in deploying and retrieving the mooring observation system. Mooring measurements at Stations C6 and C7 were kindly provided by Prof. Wei Zhao, Dr. Zhiwei Zhang, and Prof. Jiwei Tian of Ocean University of China. We gratefully acknowledge their support and suggestions on model data validation. The constructive suggestions from Prof. Lie-Yauw Oey and Dr. Christian Buckingham are greatly appreciated. Discussions with Prof. Eric Chassignet on HYCOM outputs were also particularly helpful. We are most grateful to Prof. Gert J. de Lange polishing grammar within the text. Simulated and reanalyzed products were distributed by HYCOM (http://www.hycom.org) and SSALTO/DUACS 2014 merged altimeter data were distributed by AVISO with help from CNES (www.aviso.altimetry.fr). Argo data were made available by the International Argo Program and the national programs that contribute to it (http://www.argo.ucsd.edu). The Argo Program is part of the Global Ocean Observing System. All data used in this study are provided within the supporting online material. This work was supported by the National Natural Science Foundation of China (Grant Nos. 91128206, 41576005, 91528304 & 41530964).

Supplementary material

References

  1. Adams D K, McGillicuddy D J, Zamudio L, Thurnherr A M, Liang X, Rouxel O, German C R, Mullineaux L S. 2011. Surface-generated mesoscale eddies transport deep-sea products from hydrothermal vents. Science, 332: 580–583CrossRefGoogle Scholar
  2. Boccaletti G, Ferrari R, Fox-Kemper B. 2007. Mixed layer instabilities and restratification. J Phys Oceanogr, 37: 2228–2250CrossRefGoogle Scholar
  3. Buckingham C E, Naveira Garabato A C, Thompson A F, Brannigan L, Lazar A, Marshall D P, George Nurser A J, Damerell G, Heywood K J, Belcher S E. 2016. Seasonality of submesoscale flows in the ocean surface boundary layer. Geophys Res Lett, 43: 2118–2126CrossRefGoogle Scholar
  4. Cai S Q, Long X M, Wu R H, Wang S G. 2008. Geographical and monthly variability of the first baroclinic Rossby radius of deformation in the South China Sea. J Mar Syst, 74: 711–720CrossRefGoogle Scholar
  5. Chaigneau A, Gizolme A, Grados C. 2008. Mesoscale eddies off Peru in altimeter records: Identification algorithms and eddy spatio-temporal patterns. Prog Oceanogr, 79: 106–119CrossRefGoogle Scholar
  6. Chaigneau A, Le Texier M, Eldin G, Grados C, Pizarro O. 2011. Vertical structure of mesoscale eddies in the eastern South Pacific Ocean: A composite analysis from altimetry and Argo profiling floats. J Geophys Res, 116: C11025CrossRefGoogle Scholar
  7. Chassignet E P, Hurlburt H E, Smedstad O M, Halliwell G R, Hogan P J, Wallcraft A J, Baraille R, Bleck R. 2007. The HYCOM (hybrid coordinate ocean model) data assimilative system. J Mar Syst, 65: 60–83CrossRefGoogle Scholar
  8. Chelton D B, de Szoeke R A, Schlax M G, Naggar K E, Siwertz N. 1998. Geographical variability of the first baroclinic Rossby radius of deformation. J Geophys Res, 28: 433–460Google Scholar
  9. Chelton D B, Schlax M G, Samelson R M. 2011. Global observations of nonlinear mesoscale eddies. Prog Oceanogr, 91: 167–216CrossRefGoogle Scholar
  10. Chen G X, Hou Y J, Chu X Q. 2011. Mesoscale eddies in the South China Sea: Mean properties, spatiotemporal variability, and impact on thermohaline structure. J Geophys Res, 116: C06018CrossRefGoogle Scholar
  11. de Jong M F, Bower A S, Furey H H. 2014. Two years of observations of warm-core anticyclones in the Labrador Sea and their seasonal cycle in heat and salt stratification. J Phys Oceanogr, 44: 427–444CrossRefGoogle Scholar
  12. Dewar W K. 2002. Baroclinic eddy interaction with isolated topography. J Phys Oceanogr, 32: 2789–2805CrossRefGoogle Scholar
  13. Dewar W K, Gailliard C. 1994. The dynamics of barotropically dominated rings. J Phys Oceanogr, 24: 5–29CrossRefGoogle Scholar
  14. Dietrich D E, Lin C A. 1994. Numerical studies of eddy shedding in the Gulf of Mexico. J Geophys Res, 99: 7599–7615CrossRefGoogle Scholar
  15. Dong C M, Lin X Y, Liu Y, Nencioli F, Chao Y, Guan Y, Chen D, Dickey T, McWilliams J C. 2012. Three-dimensional oceanic eddy analysis in the Southern California Bight from a numerical product. J Geophys Res, 117: C00H14Google Scholar
  16. Dong C M, McWilliams J C, Liu Y, Chen D. 2014. Global heat and salt transports by eddy movement. Nat Commun, 5: 3294CrossRefGoogle Scholar
  17. Douglass E M, Richman J G. 2015. Analysis of ageostrophy in strong surface eddies in the Atlantic Ocean. J Geophys Res-Oceans, 120: 1490–1507CrossRefGoogle Scholar
  18. Ducet N, Le Traon P Y, Reverdin G. 2000. Global high-resolution mapping of ocean circulation from TOPEX/Poseidon and ERS-1 and -2. J Geophys Res, 105: 19477–19498CrossRefGoogle Scholar
  19. Faghmous J H, Frenger I, Yao Y, Warmka R, Lindell A, Kumar V. 2015. A daily global mesoscale ocean eddy dataset from satellite altimetry. Sci Data, 2: 150028CrossRefGoogle Scholar
  20. Fu L L, Chelton D, Le Traon P Y, Morrow R. 2010. Eddy dynamics from satellite altimetry. Oceanography, 23: 14–25CrossRefGoogle Scholar
  21. Fu L L, Flierl G R. 1980. Nonlinear energy and enstrophy transfers in a realistically stratified ocean. Dyn Atmos Oceans, 4: 219–246CrossRefGoogle Scholar
  22. Gaube P, Chelton D B, Strutton P G, Behrenfeld M J. 2013. Satellite observations of chlorophyll, phytoplankton biomass, and Ekman pumping in nonlinear mesoscale eddies. J Geophys Res-Oceans, 118: 6349–6370CrossRefGoogle Scholar
  23. Gill A, Green J, Simmons A. 1974. Energy partition in the large-scale ocean circulation and the production of mid-ocean eddies. Deep Sea Res, 21: 499–528Google Scholar
  24. Halo I, Backeberg B, Penven P, Ansorge I, Reason C, Ullgren J E. 2014. Eddy properties in the Mozambique Channel: A comparison between observations and two numerical ocean circulation models. Deep-Sea Res Part II-Top Stud Oceanogr, 100: 38–53CrossRefGoogle Scholar
  25. Halliwell Jr G R, Srinivasan A, Kourafalou V, Yang H, Willey D, Le Hénaff M, Atlas R. 2014. Rigorous evaluation of a fraternal twin ocean OSSE system for the open Gulf of Mexico. J Atmos Ocean Technol, 31: 105–130CrossRefGoogle Scholar
  26. He Y H, Cai S Q, Wang S G. 2010. The correlation of the surface circulation between the Western Pacific and the South China Sea from satellite altimetry data. Int J Remote Sens, 31: 4757–4778CrossRefGoogle Scholar
  27. He Q Y, Zhan H G, Cai S Q, He Y H, Huang G L, Zhan W K. 2018. A new assessment of mesoscale eddies in the South China Sea: Surface features, three-dimensional structures, and thermohaline transports. J Geophys Res-Oceans, 123: 4906–4929CrossRefGoogle Scholar
  28. Hoskins B J. 1974. The role of potential vorticity in symmetric stability and instability. Q J R Met Soc, 100: 480–482CrossRefGoogle Scholar
  29. Hurlburt H E, Thompson J D. 1980. A numerical study of loop current intrusions and eddy shedding. J Phys Oceanogr, 10: 1611–1651CrossRefGoogle Scholar
  30. Lan J, Zhang N, Wang Y. 2013. On the dynamics of the South China Sea deep circulation. J Geophys Res-Oceans, 118: 1206–1210CrossRefGoogle Scholar
  31. Li L, Nowlin Jr. W D, Jilan S. 1998. Anticyclonic rings from the Kuroshio in the South China Sea. Deep-Sea Res Part I-Oceanogr Res Pap, 45: 1469–1482CrossRefGoogle Scholar
  32. Liang X F, Thurnherr A M. 2011. Subinertial variability in the deep ocean near the East Pacific Rise between 91° and 101°N. Geophys Res Lett, 38: L06606Google Scholar
  33. Liu Q Y, Kaneko A, Su J L. 2008. Recent progress in studies of the South China Sea circulation. J Oceanogr, 64: 753–762CrossRefGoogle Scholar
  34. Liu Z F, Zhao Y L, Colin C, Stattegger K, Wiesner M G, Huh C A, Zhang Y W, Li X J, Sompongchaiyakul P, You C F, Huang C Y, Liu J T, Siringan F P, Le K P, Sathiamurthy E, Hantoro W S, Liu J G, Tuo S T, Zhao S H, Zhou S W, He Z D, Wang Y C, Bunsomboonsakul S, Li Y L. 2016. Source-to-sink transport processes of fluvial sediments in the South China Sea. Earth-Sci Rev, 153: 238–273CrossRefGoogle Scholar
  35. Mahadevan A, Tandon A. 2006. An analysis of mechanisms for submesoscale vertical motion at ocean fronts. Ocean Model, 14: 241–256CrossRefGoogle Scholar
  36. Metzger E J, Hurlburt H E. 2001. The nondeterministic nature of kuroshio penetration and eddy shedding in the South China Sea. J Phys Oceanogr, 31: 1712–1732CrossRefGoogle Scholar
  37. Nan F, He Z G, Zhou H, Wang D. 2011a. Three long-lived anticyclonic eddies in the northern South China Sea. J Geophys Res, 116: C05002Google Scholar
  38. Nan F, Xue H, Xiu P, Chai F, Shi M, Guo P. 2011b. Oceanic eddy formation and propagation southwest of Taiwan. J Geophys Res, 116: C12045 Phys Oceanogr, 11: 1662–1672Google Scholar
  39. Oey L Y. 2008. Loop current and deep eddies. J Phys Oceanogr, 38: 1426–1449CrossRefGoogle Scholar
  40. Oey L Y, Lee H C. 2002. Deep eddy energy and topographic Rossby Waves in the Gulf of Mexico. J Phys Oceanogr, 32: 3499–3527CrossRefGoogle Scholar
  41. Qiu B, Chen S M. 2004. Seasonal modulations in the eddy field of the South Pacific Ocean. J Phys Oceanogr, 34: 1515–1527CrossRefGoogle Scholar
  42. Qiu B, Chen S M. 2005. Eddy-induced heat transport in the Subtropical North Pacific from Argo, TMI, and altimetry measurements. J Phys Oceanogr, 35: 458–473CrossRefGoogle Scholar
  43. Rivas D, Badan A, Sheinbaum J, Ochoa J, Candela J. 2008. Vertical velocity and vertical heat flux observed within loop current eddies in the Central Gulf of Mexico. J Phys Oceanogr, 38: 2461–2481CrossRefGoogle Scholar
  44. Roemmich D, Gilson J. 2001. Eddy transport of heat and thermocline waters in the North Pacific: A key to interannual/decadal climate variability? J Phys Oceanogr, 31: 675–687CrossRefGoogle Scholar
  45. Rossby T, Flagg C, Ortner P, Hu C. 2011. A tale of two eddies: Diagnosing coherent eddies through acoustic remote sensing. J Geophys Res, 116: C12017CrossRefGoogle Scholar
  46. Scott R B, Arbic B K, Chassignet E P, Coward A C, Maltrud M, Merryfield W J, Srinivasan A, Varghese A. 2010. Total kinetic energy in four global eddying ocean circulation models and over 5000 current meter records. Ocean Model, 32: 157–169CrossRefGoogle Scholar
  47. Shu Y Q, Chen J, Li S, Wang Q, Yu J C, Wang D X. 2019. Field-observation for an anticyclonic mesoscale eddy consisted of twelve gliders and sixty-two expendable probes in the northern South China Sea during summer 2017. Sci China Earth Sci, 62: 451–458CrossRefGoogle Scholar
  48. Shu Y Q, Xue H J, Wang D X, Xie Q, Cai S Q. 2016. Persistent and energetic bottom-trapped topographic Rossby waves observed in the southern South China Sea. Sci Rep, 6: 24338CrossRefGoogle Scholar
  49. Smith D C. 1986. A numerical study of loop current eddy interaction with topography in the Western Gulf of Mexico. J Phys Oceanogr, 16: 1260–1272CrossRefGoogle Scholar
  50. Smith D C, O’Brien J J. 1983. The interaction of a two-layer isolated mesoscale eddy with bottom topography. J Phys Oceanogr, 13: 1681–1697CrossRefGoogle Scholar
  51. Souza J M A C, de Boyer Montegut C, Cabanes C, Klein P. 2011. Estimation of the Agulhas ring impacts on meridional heat fluxes and transport using ARGO floats and satellite data. Geophys Res Lett, 38: L21602CrossRefGoogle Scholar
  52. Spall M A. 2000. Generation of strong mesoscale eddies by weak ocean gyres. J Mar Res, 58: 97–116CrossRefGoogle Scholar
  53. Sutyrin G. 2015. Generation of deep eddies by a turning baroclinic jet. Deep-Sea Res Part I-Oceanogr Res Pap, 101: 1–6CrossRefGoogle Scholar
  54. Sutyrin G G, Rowe G D, Rothstein L M, Ginis I. 2003. Baroclinic eddy interactions with continental slopes and shelves. J Phys Oceanogr, 33: 283–291CrossRefGoogle Scholar
  55. Sutyrin G G, Grimshaw R. 2005. Frictional effects on the deep-flow feedback on the -drift of a baroclinic vortex over sloping topography. Deep-Sea Res Part I-Oceanogr Res Pap, 52: 2156–2167CrossRefGoogle Scholar
  56. Taylor J R, Ferrari R. 2010. Buoyancy and wind-driven convection at mixed layer density fronts. J Phys Oceanogr, 40: 1222–1242CrossRefGoogle Scholar
  57. Thomas L N, Tandon A, Mahadevan A. 2008. Submesoscale processes and dynamics, Ocean Modeling in an Eddying Regime, in Ocean Modeling in an Eddying Regime. Geophys Monogr Ser, 177: 17–38Google Scholar
  58. Thomas L N, Taylor J R, Ferrari R, Joyce T M. 2013. Symmetric instability in the Gulf Stream. Deep-Sea Res Part II-Top Stud Oceanogr, 91: 96–110CrossRefGoogle Scholar
  59. Thompson A F, Lazar A, Buckingham C, Naveira Garabato A C, Damarell G M, Heywood K J. 2016. Open-ocean submesoscale motions: A full seasonal cycle of mixed layer instabilities from gliders. J Phys Oceanogr, 46: 1285–1307CrossRefGoogle Scholar
  60. Wang D X, Xu H Z, Lin J, Hu J Y, Wang D X. 2008. Anticyclonic eddies in the northeastern South China Sea during winter 2003/2004. J Oceanogr, 64: 925–935CrossRefGoogle Scholar
  61. Wang G H, Su J L, Chu P C. 2003. Mesoscale eddies in the South China Sea observed with altimeter data. Geophys Res Lett, 30: 2121CrossRefGoogle Scholar
  62. Wortham C. 2013. A multi-dimensional spectral description of ocean variability with applications. Doctoral Dissertation. Massachusetts: Massachusetts Institute of Technology and Woods Hole Oceanographic Institution. 69–96Google Scholar
  63. Wu C R, Chiang T L. 2007. Mesoscale eddies in the northern South China Sea. Deep-Sea Res Part II-Top Stud Oceanogr, 54: 1575–1588CrossRefGoogle Scholar
  64. Wunsch C. 1999. Where do ocean eddy heat fluxes matter? J Geophys Res, 104: 13235–13249CrossRefGoogle Scholar
  65. Wunsch C. 2009. The oceanic variability spectrum and transport trends. Atmosphere-Ocean, 47: 4281–4291CrossRefGoogle Scholar
  66. Wyrtki K, Magaard L, Hager J. 1976. Eddy energy in the oceans. J Geophys Res, 81: 2641–2646CrossRefGoogle Scholar
  67. Xie Q, Xiao J G, Wang D X, Yu Y. 2013. Analysis of deep-layer and bottom circulations in the South China Sea based on eight quasi-global ocean model outputs. Chin Sci Bull, 58: 4000–4011CrossRefGoogle Scholar
  68. Xiu P, Chai F, Shi L, Xue H, Chao Y. 2010. A census of eddy activities in the South China Sea during 1993–2007. J Geophys Res, 115: C03012CrossRefGoogle Scholar
  69. Xue H J, Chai F, Pettigrew N, Xu D, Shi M, Xu J. 2004. Kuroshio intrusion and the circulation in the South China Sea. J Geophys Res, 109: C02017Google Scholar
  70. Zhang Y W, Liu Z F, Zhao Y L, Li J R, Liang X F. 2015. Effect of surface mesoscale eddies on deep-sea currents and mixing in the northeastern South China Sea. Deep-Sea Res Part II-Top Stud Oceanogr, 122: 6–14CrossRefGoogle Scholar
  71. Zhang Y W, Liu Z F, Zhao Y L, Wang W G, Li J R, Xu J P. 2014. Mesoscale eddies transport deep-sea sediments. Sci Rep, 4: 5937CrossRefGoogle Scholar
  72. Zhang Z W, Tian J W, Qiu B, Zhao W, Chang P, Wu D, Wan X. 2016. Observed 3D structure, generation, and dissipation of oceanic mesoscale eddies in the South China Sea. Sci Rep, 6: 24349CrossRefGoogle Scholar
  73. Zhang Z G, Wang W, Qiu B. 2014. Oceanic mass transport by mesoscale eddies. Science, 345: 322–324CrossRefGoogle Scholar
  74. Zhang Z W, Zhao W, Qiu B, Tian J W. 2017. Anticyclonic eddy sheddings from Kuroshio loop and the accompanying cyclonic eddy in the northeastern South China Sea. J Phys Oceanogr, 47: 1243–1259CrossRefGoogle Scholar
  75. Zhang Z W, Zhao W, Tian J W, Liang X F. 2013. A mesoscale eddy pair southwest of Taiwan and its influence on deep circulation. J Geophys Res-Oceans, 118: 6479–6494CrossRefGoogle Scholar
  76. Zhao W, Zhou C, Tian J W, Yang Q X, Wang B, Xie L L, Qu T D. 2014. Deep water circulation in the Luzon Strait. J Geophys Res-Oceans, 119: 790–804CrossRefGoogle Scholar
  77. Zhao Y L, Liu Z F, Zhang Y W, Li J R, Wang M, Wang W G, Xu J P. 2015. In situ observation of contour currents in the northern South China Sea: Applications for deepwater sediment transport. Earth Planet Sci Lett, 430: 477–485CrossRefGoogle Scholar

Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Meng Wang
    • 1
  • Yanwei Zhang
    • 1
    Email author
  • Zhifei Liu
    • 1
  • Yulong Zhao
    • 1
  • Jianru Li
    • 1
  1. 1.State Key Laboratory of Marine GeologyTongji UniversityShanghaiChina

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