Three-dimensional structure of an observed cyclonic mesoscale eddy in the Northwest Pacific and its assimilation experiment

Jun Dai; Huizan Wang; Weimin Zhang; Pinqiang Wang; Tengling Luo

doi:10.1007/s13131-021-1810-6

Volume 40 Issue 5

May 2021

Turn off MathJax

Article Contents

Article Navigation > Acta Oceanologica Sinica > 2021 > 40(5): 1-19

Jun Dai, Huizan Wang, Weimin Zhang, Pinqiang Wang, Tengling Luo. Three-dimensional structure of an observed cyclonic mesoscale eddy in the Northwest Pacific and its assimilation experiment[J]. Acta Oceanologica Sinica, 2021, 40(5): 1-19. doi: 10.1007/s13131-021-1810-6

Citation:

Jun Dai, Huizan Wang, Weimin Zhang, Pinqiang Wang, Tengling Luo. Three-dimensional structure of an observed cyclonic mesoscale eddy in the Northwest Pacific and its assimilation experiment[J]. Acta Oceanologica Sinica, 2021, 40(5): 1-19. doi: 10.1007/s13131-021-1810-6

Citation:

Jun Dai, Huizan Wang, Weimin Zhang, Pinqiang Wang, Tengling Luo. Three-dimensional structure of an observed cyclonic mesoscale eddy in the Northwest Pacific and its assimilation experiment[J]. Acta Oceanologica Sinica, 2021, 40(5): 1-19. doi: 10.1007/s13131-021-1810-6

PDF( 27116 KB)

Three-dimensional structure of an observed cyclonic mesoscale eddy in the Northwest Pacific and its assimilation experiment

doi: 10.1007/s13131-021-1810-6

College of Meteorology and Oceanography, National University of Defense Technology, Changsha 410073, China

Funds: The National Key R&D Program of China under contract No. 2018YFC1406202; the National Natural Science Foundation of China under contract Nos 41811530301, 41830964 and 41976188.

More Information

Corresponding author: wanghuizan@126.com
Received Date: 2020-08-06
Accepted Date: 2020-12-08

Available Online: 2021-04-26

Publish Date: 2021-05-01

Abstract

Abstract

Mesoscale eddies play an important role in modulating the ocean circulation. Many previous studies on the three-dimensional structure of mesoscale eddies were mainly based on composite analysis, and there are few targeted observations for individual eddies. A cyclonic eddy surveyed during an oceanographic cruise in the Northwest Pacific Ocean is investigated in this study. The three-dimensional structure of this cyclonic eddy is revealed by observations and simulated by the four-dimensional variational data assimilation (4DVAR) system combined with the Regional Ocean Modeling System. The observation and assimilation results together present the characteristics of the cyclonic eddy. The cold eddy has an obvious dual-core structure of temperature anomaly. One core is at 50–150 m and another is at 300–550 m, which both have the average temperature anomaly of approximately −3.5°C. The salinity anomaly core is between 250 m and 500 m, which is approximately −0.3. The horizontal velocity structure is axis-asymmetric and it is enhanced on the eastern side of the cold eddy. In the assimilation experiment, sea level anomaly, sea surface temperature, and in situ measurements are assimilated into the system, and the results of assimilation are close to the observations. Based on the high-resolution assimilation output results, the study also diagnoses the vertical velocity in the mesoscale eddy, which reaches the maximum of approximately 10 m/d. The larger vertical velocity is found to be distributed in the range of 0.5 to 1 time of the normalized radius of the eddy. The validation of the simulation result shows that the 4DVAR method is effective to reconstruct the three-dimensional structure of mesoscale eddy and the research is an application to study the mesoscale eddy in the Northwest Pacific by combining observation and assimilation methods.
- mesoscale eddy,
- three-dimensional structure,
- 4DVAR assimilation,
- vertical velocity

FullText(HTML)

References(56)

References

[1]	Barth A, Beckers J M, Troupin C, et al. 2014. Divand-1.0: n-dimensional variational data analysis for ocean observations. Geoscientific Model Development, 7(1): 225–241. doi: 10.5194/gmd-7-225-2014
[2]	Beismann J O, Käse R H, Lutjeharms J R E. 1999. On the influence of submarine ridges on translation and stability of Agulhas rings. Journal of Geophysical Research: Oceans, 104(C4): 7897–7906. doi: 10.1029/1998JC900127
[3]	Chaigneau A, Gizolme A, Grados C. 2008. Mesoscale eddies off Peru in altimeter records: Identification algorithms and eddy spatio-temporal patterns. Progress in Oceanography, 79(2–4): 106–119
[4]	Chaigneau A, Le Texier M, Eldin G, et al. 2011. Vertical structure of mesoscale eddies in the eastern South Pacific Ocean: A composite analysis from altimetry and Argo profiling floats. Journal of Geophysical Research: Oceans, 116(C11): C11025. doi: 10.1029/2011JC007134
[5]	Chelton D B, Schlax M G, Samelson R M. 2011. Global observations of nonlinear mesoscale Eddies. Progress in Oceanography, 91(2): 167–216. doi: 10.1016/j.pocean.2011.01.002
[6]	Chen Gengxin, Hou Yijun, Chu Xiaoqing. 2011. Mesoscale eddies in the South China Sea: Mean properties, spatiotemporal variability, and impact on thermohaline structure. Journal of Geophysical Research: Oceans, 116(C6): C06018
[7]	Dai Jun, Wang Huizan, Zhang Weimin, et al. 2020. Observed spatiotemporal variation of three-dimensional structure and heat/salt transport of anticyclonic mesoscale eddy in Northwest Pacific. Journal of Oceanology and Limnology, 38(6): 1654–1675. doi: 10.1007/s00343-019-9148-z
[8]	Dong Di, Brandt P, Chang Ping, et al. 2017. Mesoscale eddies in the northwestern Pacific Ocean: Three-dimensional eddy structures and heat/salt transports. Journal of Geophysical Research: Oceans, 122(12): 9795–9813. doi: 10.1002/2017JC013303
[9]	Early J J, Samelson R M, Chelton D B. 2011. The evolution and propagation of quasigeostrophic ocean eddies. Journal of Physical Oceanography, 41(8): 1535–1555. doi: 10.1175/2011JPO4601.1
[10]	Ferrari R, Wunsch C. 2009. Ocean circulation kinetic energy: Reservoirs, sources, and sinks. Annual Review of Fluid Mechanics, 41: 253–282. doi: 10.1146/annurev.fluid.40.111406.102139
[11]	Ferron B. 2011. A 4D-variational approach applied to an eddy-permitting North Atlantic configuration: Synthetic and real data assimilation of altimeter observations. Ocean Modelling, 39(3–4): 370–385
[12]	Gao Shan, Wang Fan, Li Mingkui, et al. 2008. Application of altimetry data assimilation on mesoscale eddies simulation. Science in China Series D: Earth Sciences, 51(1): 124–151
[13]	He Yinghui, Cai Shuqun, Wang Dongxiao, et al. 2015. A model study of Luzon cold eddies in the northern South China Sea. Deep Sea Research Part I: Oceanographic Research Papers, 97: 107–123. doi: 10.1016/j.dsr.2014.12.007
[14]	He Zhongjie, Xie Yuanfu, Li Wei, et al. 2008. Application of the sequential three-dimensional variational method to assimilating SST in a global ocean model. Journal of Atmospheric and Oceanic Technology, 25(6): 1018–1033. doi: 10.1175/2007JTECHO540.1
[15]	Hoskins B J, Draghici I, Davies H C. 1978. A new look at the ω-equation. Quarterly Journal of the Royal Meteorological Society, 104(439): 31–38. doi: 10.1002/qj.49710443903
[16]	Kamenkovich V M, Leonov Y P, Nechaev D A, et al. 1996. On the influence of bottom topography on the Agulhas eddy. Journal of Physical Oceanography, 26(6): 892–912. doi: 10.1175/1520-0485(1996)026<0892:OTIOBT>2.0.CO;2
[17]	Li Cheng, Zhang Zhiwei, Zhao Wei, et al. 2017. A statistical study on the subthermocline submesoscale eddies in the northwestern Pacific Ocean based on Argo data. Journal of Geophysical Research: Oceans, 122(5): 3586–3598. doi: 10.1002/2016JC012561
[18]	Lin Xiayan, Guan Yuping, Liu Yu. 2013. Three-dimensional structure and evolution process of Dongsha Cold Eddy during autumn 2000. Journal of Tropical Oceanography (in Chinese), 32(2): 55–65
[19]	Liu Danian, Wang Fan, Zhu Jiang, et al. 2020. Impact of assimilation of moored velocity data on low-frequency current estimation in Northwestern Tropical Pacific. Journal of Geophysical Research: Oceans, 125(9): e2019JC015829
[20]	Liu Danian, Zhu Jiang, Shu Yeqiang, et al. 2018a. Targeted observation analysis of a Northwestern Tropical Pacific Ocean mooring array using an ensemble-based method. Ocean Dynamics, 68(9): 1109–1119. doi: 10.1007/s10236-018-1188-y
[21]	Liu Danian, Zhu Jiang, Shu Yeqiang, et al. 2018b. Model-based assessment of a Northwestern Tropical Pacific moored array to monitor intraseasonal variability. Ocean Modelling, 126: 1–12. doi: 10.1016/j.ocemod.2018.04.001
[22]	Ma Xiaohui, Jing Zhao, Chang Ping, et al. 2016. Western boundary currents regulated by interaction between ocean eddies and the atmosphere. Nature, 535(7613): 533–537. doi: 10.1038/nature18640
[23]	Mahadevan A. 2016. The impact of submesoscale physics on primary productivity of plankton. Annual Review of Marine Science, 8: 161–184. doi: 10.1146/annurev-marine-010814-015912
[24]	Mahadevan A, Thomas L N, Tandon A. 2008. Comment on “Eddy/wind interactions stimulate extraordinary mid-ocean plankton blooms”. Science, 320(5875): 448
[25]	Martin A P, Richards K J. 2001. Mechanisms for vertical nutrient transport within a North Atlantic mesoscale eddy. Deep Sea Research Part II: Topical Studies in Oceanography, 48(4–5): 757–773
[26]	McGillicuddy D J Jr, Anderson L A, Bates N R, et al. 2007. Eddy/wind interactions stimulate extraordinary mid-ocean plankton blooms. Science, 316(5827): 1021–1026. doi: 10.1126/science.1136256
[27]	McWilliams J C, Graves L P, Montgomery M T. 2003. A formal theory for vortex rossby waves and vortex evolution. Geophysical & Astrophysical Fluid Dynamics, 97(4): 275–309
[28]	Moore A M, Arango H G, Broquet G, et al. 2011a. The Regional Ocean Modeling System (ROMS) 4-dimensional variational data assimilation systems: Part I—System overview and formulation. Progress in Oceanography, 91(1): 34–49. doi: 10.1016/j.pocean.2011.05.004
[29]	Moore A M, Arango H G, Broquet G, et al. 2011b. The Regional Ocean Modeling System (ROMS) 4-dimensional variational data assimilation systems: Part II—performance and application to the California Current System. Progress in Oceanography, 91(1): 50–73. doi: 10.1016/j.pocean.2011.05.003
[30]	Nardelli B B. 2013. Vortex waves and vertical motion in a mesoscale cyclonic eddy. Journal of Geophysical Research: Oceans, 118(10): 5609–5624. doi: 10.1002/jgrc.20345
[31]	Ni Qinbiao. 2014. Statistical characteristics and composite three-dimensional structures of mesoscale eddies near the Luzon Strait (in Chinese) [dissertation]. Xiamen: Xiamen University
[32]	Ni Qinbiao. 2019. Study on eddy movement in the ocean (in Chinese) [dissertation]. Xiamen: Xiamen University
[33]	Oka E, Kouketsu S, Toyama K, et al. 2011. Formation and subduction of central mode water based on profiling float data, 2003–08. Journal of Physical Oceanography, 41(1): 113–129. doi: 10.1175/2010JPO4419.1
[34]	Powell B S, Arango H G, Moore A M, et al. 2008. 4DVAR data assimilation in the intra-Americas Sea with the Regional Ocean Modeling System (ROMS). Ocean Modeling, 25(3–4): 173–188
[35]	Qiu Bo, Chen Shuiming, Klein P, et al. 2020. Reconstructing upper-ocean vertical velocity field from sea surface height in the presence of unbalanced motion. Journal of Physical Oceanography, 50(1): 55–79. doi: 10.1175/JPO-D-19-0172.1
[36]	Rubio A, Barnier B, Jordá G, et al. 2009. Origin and dynamics of mesoscale eddies in the Catalan Sea (NW Mediterranean): Insight from a numerical model study. Journal of Geophysical Research: Oceans, 114(C6): C06009
[37]	Sasaki H, Klein P, Qiu Bo, et al. 2014. Impact of oceanic-scale interactions on the seasonal modulation of ocean dynamics by the atmosphere. Nature Communications, 5: 5636. doi: 10.1038/ncomms6636
[38]	Shu Yeqiang, Chen Ju, Li Shuo, et al. 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. Science China Earth Sciences, 62(2): 451–458. doi: 10.1007/s11430-018-9239-0
[39]	Shu Yeqiang, Wang Dongxiao, Zhu Jiang, et al. 2011. The 4-D structure of upwelling and Pearl River plume in the northern South China Sea during summer 2008 revealed by a data assimilation model. Ocean Modelling, 36(3–4): 228–241
[40]	Souza J M A C, De Boyer Montégut C, Le Traon P Y. 2011. Comparison between three implementations of automatic identification algorithms for the quantification and characterization of mesoscale eddies in the South Atlantic Ocean. Ocean Science, 7(3): 317–334. doi: 10.5194/os-7-317-2011
[41]	Thompson P D. 2010. Reduction of analysis error through constraints of dynamical consistency. Journal of Applied Meteorology, 8(5): 738–742
[42]	Troupin C, Barth A, Sirjacobs D, et al. 2012. Generation of analysis and consistent error fields using the Data Interpolating Variational Analysis (DIVA). Ocean Modelling, 52–53: 90–101
[43]	Wang Guihua, Su Jilan, Chu P C. 2003. Mesoscale eddies in the South China Sea observed with altimeter data. Geophysical Research Letters, 30(21): 2121. doi: 10.1029/2003GL018532
[44]	Wang Lei, Gan Jianping. 2014. Delving into three-dimensional structure of the West Luzon Eddy. Deep Sea Research Part I: Oceanographic Research Papers, 90: 48–61. doi: 10.1016/j.dsr.2014.04.011
[45]	Warner J C, Sherwood C R, Arango H G, et al. 2005. Performance of four turbulence closure models implemented using a generic length scale method. Ocean Modelling, 8(1–2): 81–113
[46]	Xu Dazhi. 2012. Research on predictability of mesoscale eddies in the northern South China Sea based on data assimilation (in Chinese) [dissertation]. Guangzhou: South China Sea Institute of Oceanology
[47]	Yang Guang, Wang Fan, Li Yuanlong, et al. 2013. Mesoscale eddies in the northwestern subtropical Pacific Ocean: Statistical characteristics and three-dimensional structures. Journal of Geophysical Research: Oceans, 118(4): 1906–1925. doi: 10.1002/jgrc.20164
[48]	Zhang Zhiwei, Li Peiliang, Xu Lixiao, et al. 2015. Subthermocline eddies observed by rapid-sampling Argo floats in the subtropical northwestern Pacific Ocean in Spring 2014. Geophysical Research Letters, 42(15): 6438–6445. doi: 10.1002/2015GL064601
[49]	Zhang Wenzhou, Ni Qinbiao, Xue Huijie. 2018. Composite eddy structures on both sides of the Luzon Strait and influence factors. Ocean Dynamics, 68(11): 1527–1541. doi: 10.1007/s10236-018-1207-z
[50]	Zhang Zhiwei, Tian Jiwei, Qiu Bo, et al. 2016. Observed 3D structure, generation, and dissipation of oceanic mesoscale eddies in the South China Sea. Scientific Reports, 6: 24349. doi: 10.1038/srep24349
[51]	Zhang Zhengguang, Wang Wei, Qiu Bo. 2014. Oceanic mass transport by mesoscale eddies. Science, 345(6194): 322–324. doi: 10.1126/science.1252418
[52]	Zhang Zhiwei, Zhang Xincheng, Qiu Bo, et al. 2020a. Submesoscale currents in the subtropical upper ocean observed by long-term high-resolution mooring arrays. Journal of Physical Oceanography, 51(1): 187–206. doi: 10.1175/JPO-D-20-0100.1
[53]	Zhang Zhiwei, Zhang Yuchen, Qiu Bo, et al. 2020b. Spatiotemporal characteristics and generation mechanisms of submesoscale currents in the northeastern South China Sea revealed by numerical simulations. Journal of Geophysical Research: Oceans, 125(2): e2019JC015404
[54]	Zhang Zhengguang, Zhang Yu, Wang Wei, et al. 2013. Universal structure of mesoscale eddies in the ocean. Geophysical Research Letters, 40(14): 3677–3681. doi: 10.1002/grl.50736
[55]	Zhao Fu, Zhang Yunfei, Zhu Xueming, et al. 2017. An assimilative numerical study of the paired cold and warm mesoscale eddies during winter in the southwest of Taiwan. Marine Forecasts (in Chinese), 34(5): 1–15
[56]	Zhong Yisen, Bracco A, Tian Jiwei, et al. 2017. Observed and simulated submesoscale vertical pump of an anticyclonic eddy in the South China Sea. Scientific Reports, 7: 44011. doi: 10.1038/srep44011