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Journal of Tropical Oceanography >

2016 , Vol. 35 >Issue 4: 11 - 20

DOI: https://doi.org/10.11978/2015126

Marine Hydrography

The dynamic characteristics of deep meridional overturning circulation in the Indian Ocean based on six reanalysis datasets

  • HUANG Xumei ,
  • WANG Weiqiang ,
  • LIU Hailong
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  • 1. State Key Laboratory of Tropical Oceanography (South China Sea Institute of Oceanology, Chinese Academy of Sciences), Guangzhou 510301, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China;
    3. State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China;

Received date: 2015-10-14

  Online published: 2016-08-04

Supported by

The Strategic Priority Research Program of the Chinese Academy of Sciences (grant no; XDA11010301); the National Natural Science Foundation of China (41376024); the National Key Program for Developing Basic Sciences (2013CB956204)

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Abstract

The dynamic characteristics of time-mean meridional overturning circulation in the Indian Ocean was examined using six reanalysis datasets. The results showed consistent time-mean features of the deep meridional overturning circulation, which is an anticlockwise overturning cell with inflows in the bottom and deep layers and outflows in the intermediate and upper layers. Dynamic decomposition of meridional overturning circulation was applied to examine the similarities and differences of every dynamic component. The structure of Ekman component is an anticlockwise overturning cell in the South Indian Ocean with maximum strength at ~10°S. In the region south of 10°S, geostrophic and external components show clockwise and anticlockwise overturning cells, respectively, they both reach maximum strengths at ~27°S. Based on different products of heat and momentum fluxes used, the dynamic components resulted from the six datasets show some inconsistent features as follows. The overall structures of Ekman component are similar since the wind fields of the six datasets have few differences. The discrepancies of the geostrophic component in the six datasets are due to the strength of the baroclinic flows in the interior ocean and the structure of the western boundary current: the greater the baroclinic flows in the interior ocean, the stronger the strength of the geostrophic component; the wider the western boundary current, the greater impact on the baroclinic flows in the interior ocean, and then on the strength of the geostrophic component. The strength of the external component is affected by the intensity of the western boundary current: the greater the western boundary current, the stronger the strength of the external component.

Key words： deep meridional overturning circulation; Ekman component; geostrophic component; external component; time mean

Cite this article

HUANG Xumei , WANG Weiqiang , LIU Hailong . The dynamic characteristics of deep meridional overturning circulation in the Indian Ocean based on six reanalysis datasets[J]. Journal of Tropical Oceanography, 2016 , 35(4) : 11 -20 . DOI: 10.11978/2015126

References

[1] ADCROFT A, HILL C, MARSHALL J, 1997. Representation of topography by shaved cells in a height coordinate ocean model[J]. Monthly Weather Review, 125(9): 2293-2315.
[2] BEAL L M, BRYDEN H L, 1999. The velocity and vorticity structure of the Agulhas Current at 32˚S[J]. Journal of Geophysical Research: Oceans (1978-2012), 104(C3): 5151-5176.
[3] BEHRINGER D W, XUE Y, 2004. Evaluation of the global ocean data assimilation system at NCEP: The Pacific Ocean[C]//Eighth Symposium on Integrated Observing and Assimilation Systems for Atmosphere, Oceans, and Land Surface. Seattle: American Meteorological Society.
[4] CARTON J A, GIESE B S, GRODSKY S A, 2005. Sea level rise and the warming of the oceans in the Simple Ocean Data Assimilation (SODA) ocean reanalysis[J]. Journal of Geophysical Research: Oceans (1978-2012): 110(C9), doi:10.1029/2004JC 002817.
[5] CARTON J A, GIESE B S, 2008. A reanalysis of ocean climate using Simple Ocean Data Assimilation (SODA)[J]. Monthly Weather Review, 136(8): 2999-3017.
[6] DRIJFHOUT S S, GARABATO A C N, 2008. The zonal dimension of the Indian Ocean meridional overturning circulation[J]. Journal of Physical Oceanography, 38(2): 359-379.
[7] FENG X, LIU H L, WANG F C, et al, 2013. Indonesian Throughflow in an eddy-resolving ocean model[J]. Chinese Science Bulletin, 58(35): 4504-4514.
[8] HIRSCHI J, MAROTZKE J, 2007. Reconstructing the meridional overturning circulation from boundary densities and the zonal wind stress[J]. Journal of Physical Oceanography, 37(3): 743-763.
[9] KÖHL A, STAMMER D, 2008. Variability of the meridional overturning in the North Atlantic from the 50-year GECCO state estimation[J]. Journal of Physical Oceanography, 38(9): 1913-1930.
[10] LEE T, MAROTZKE J, 1998. Seasonal cycles of meridional overturning and heat transport of the Indian Ocean[J]. Journal of Physical Oceanography, 28(5): 923-943.
[11] LIU H L, LIN P F, YU Y Q, et al, 2012. The baseline evaluation of LASG/IAP climate system ocean model (LICOM) version 2[J]. Acta Meteorologica Sinica, 26(3): 318-329.
[12] MANTYLA A W, REID J L, 1995. On the origins of deep and bottom waters of the Indian-Ocean[J]. Journal of Geophysical Research, 100 (C2): 2417-2439.
[13] MENEMENLIS D, CAMPIN J M, HEIMBACH P, et al, 2008. ECCO2: High resolution global ocean and sea ice data synthesis[C]//American Geophysical Union, Fall Meeting 2008. San Francisco, CA: AGU, 31: 13-21.
[14] RINTOUL S R, BALMESEDA M, CUNNINGHAM S, et al, 2010. Deep circulation and meridional overturning: Recent progress and strategy for sustained observations[J]. Proceedings of OceanObs’ 09: Sustained Ocean Observations and Information for Society. Washington, DC: European Space Agency: 175-191.
[15] ROBBINS P E, TOOLE J M, 1997. The dissolved silica budget as a constraint on the meridional overturning circulation of the Indian Ocean[J]. Deep Sea Research Part Ⅰ: Oceanographic Research Papers, 44(5): 879-906.
[16] SCHOTT F A, MCCREARY J P, 2001. The monsoon circulation of the Indian Ocean[J]. Progress in Oceanography, 2001, 51(1): 1-123.
[17] SIME L C, STEVENS D P, HEYWOOD K J, et al, 2006. A decomposition of the Atlantic meridional overturning[J]. Journal of Physical Oceanography, 36(12): 2253-2270.
[18] SMITH W H, SANDWELL D T, 1997. Global sea floor topography from satellite altimetry and ship depth soundings[J]. Science, 277(5334): 1956-1962.
[19] TALLEY L D, 2013. Closure of the global overturning circulation through the Indian, Pacific, and Southern Oceans: Schematics and transports[J]. Oceanography, 26(1): 80-97.
[20] TOOLE J M, WARREN B A, 1993. A hydrographic section across the subtropical South Indian Ocean[J]. Deep Sea Research Part Ⅰ: Oceanographic Research Papers, 40(10): 1973-2019.
[21] WANG W Q, KÖHL A, STAMMER D, 2010. Estimates of global ocean volume transports during 1960 through 2001[J]. Geophysical Research Letters, 37(15): L15601.
[22] WANG W Q, KÖHL A, STAMMER D, 2012. The deep meridional overturning circulation in the Indian Ocean inferred from the GECCO synthesis[J]. Dynamics of Atmospheres and Oceans, 58: 44-61.
[23] WANG W Q, ZHU X H, WANG C Z, et al, 2014. Deep meridional overturning circulation in the Indian ocean and its relation to Indian ocean dipole[J]. Journal of Climate, 27(12): 4508-4520.
[24] YU Y Q, LIU H L, LIN P F, 2012. A quasi-global 1/10˚ eddy-resolving ocean general circulation model and its preliminary results[J]. Chinese Science Bulletin, 57(30): 3908-3916.
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