Climate Dynamics

, Volume 47, Issue 5–6, pp 1629–1646 | Cite as

Dynamical and thermodynamical analysis of the South China Sea winter cold tongue

  • Bijoy Thompson
  • Pavel Tkalich
  • Paola Malanotte-Rizzoli
  • Bastien Fricot
  • Juliette Mas
Article

Abstract

Spatial distribution of the South China Sea (SCS) surface temperature shows strong cold anomalies over the Sunda Shelf during the boreal winter season. The band of low sea surface temperature (SST) region located south/southeast of Vietnam is called as the winter cold tongue (CT) in the SCS. Using observational and re-analysis datasets a comprehensive investigation of the dynamical and thermodynamical processes associated with the evolution of SCS CT is performed in this study. The role and relative importance of wind-driven ocean transports, air–sea heat fluxes and oceanic processes are explored. The north-south Sverdrup transport demonstrates strong southward transport during the northeast monsoon period aiding the SST cooling by bringing relatively cold water from the north. The zonal and meridional Ekman transports exhibit relatively weak westward and northward transports to the CT region during this period. The study suggests that wind-driven ocean transports have a significant role in regulating the shape and spatial extent of the CT. The heat budget analysis revealed that net surface heat flux decrease during the northeast monsoon acts as the primary cooling mechanism responsible for the development of the SCS CT, while the horizontal advection of cold water by the western boundary current along the coast of Vietnam plays a secondary role. The wintertime SST anomalies over the CT region are significantly linked to the Nino3 index. Most of the warming/cooling events in the SST anomalies coincide with the El Nino/La Nina phenomena in the Pacific Ocean.

Keywords

South China Sea Cold tongue Wind-driven transport Heat budget 

References

  1. Alexander MA, Scott JD (2008) The role of Ekman Ocean heat transport in the Northern Hemisphere response to ENSO. J Clim 21:5688–5707CrossRefGoogle Scholar
  2. Alexander MA, Bladé I, Newman M, Lanzante JR, Lau N-C, Scott JD (2002) The atmospheric bridge: the influence of ENSO teleconnections on air–sea interaction over the global oceans. J Clim 15:2205–2231CrossRefGoogle Scholar
  3. Berry DI, Kent EC (2009) A new air–sea interaction gridded dataset from ICOADS with uncertainty estimates. Bull Am Meteorol Soc 90:645–656CrossRefGoogle Scholar
  4. Berry DI, Kent EC (2011) Air–sea fluxes from ICOADS: the construction of a new gridded dataset with uncertainty estimates. Int J Clim 31:987–1001CrossRefGoogle Scholar
  5. Carton JA, Giese BS (2008) A reanalysis of ocean climate using Simple Ocean Data Assimilation (SODA). Mon Wea Rev 136:2999–3017CrossRefGoogle Scholar
  6. Chao CY, Shaw PT, Wu SY (1996) El Nino modulations of the South China Sea circulation. Prog Oceanogr 38:51–93CrossRefGoogle Scholar
  7. Chen J-M, Chang C-P, Li T (2003) Annual cycle of the South China Sea surface temperature using the NCEP/NCAR reanalysis. J Meteorol Soc Jpn 81:879–884CrossRefGoogle Scholar
  8. Chu PC, Lu S, Chen Y (1997) Temporal and spatial variabilities of the South China Sea surface temperature anomaly. J Geophys Res 102: 20, 937–20, 955Google Scholar
  9. de Boyer MC, Vialard J, Shenoi SSC, Shankar D, Durand F, Ethé C, Madec G (2007) Simulated seasonal and interannual variability of mixed layer heat budget in the northern Indian Ocean. J Clim 20:3249–3268CrossRefGoogle Scholar
  10. Dee DP et al (2011) The ERA-Interim reanalysis: configuration and performance of the data assimilation system. Q J R Meteorol Soc 137:553–597CrossRefGoogle Scholar
  11. Fang G, Chen H, Wei Z, Wang Y, Wang X, Li C (2006) Trends and interannual variability of the South China Sea surface winds, surface height, and surface temperature in the recent decade. J Geophys Res 111:C11S16. doi:10.1029/2005JC003276 CrossRefGoogle Scholar
  12. Huang E, Tian TJ, Steinke S (2011) Millennial-scale dynamics of the winter cold tongue in the southern South China Sea over the past 26 ka and the East Asian winter monsoon. Quat Res 75(1):196–204CrossRefGoogle Scholar
  13. Jerlov NG (1968) Optical oceanography. Elsevier, New York, p 194Google Scholar
  14. Jhun J-G, Lee E-J (2004) A new East Asian winter monsoon index and associated characteristics of the winter monsoon. J Clim 17:711–726CrossRefGoogle Scholar
  15. Klein SA, Soden BJ, Lau N-C (1999) Remote sea surface variations during ENSO: evidence for a tropical atmospheric bridge. J Clim 12(4):917–932CrossRefGoogle Scholar
  16. Koseki S, Koh T-Y, Teo C-K (2013) Effects of the cold tongue in the South China Sea on the monsoon, diurnal cycle and rainfall in the Maritime Continent. Q J R Meteorol Soc 139:1566–1582CrossRefGoogle Scholar
  17. Levitus S (1987) Meridional Ekman heat fluxes for the world ocean and individual ocean basins. J Phys Oceanogr 17:1484–1492CrossRefGoogle Scholar
  18. Liu WT, Xie X (1999) Space based observations of the seasonal changes of the south Asian monsoon and oceanic responses. Geophys Res Lett 26:1473–1476CrossRefGoogle Scholar
  19. Liu Q, Jiang X, Xie S-P, Liu WT (2004) A gap in the Indo-Pacific warm pool over the South China Sea in boreal winter: seasonal development and interannual variability. J Geophys Res (Oceans) 109:C07012. doi:10.1029/2003JC002179 Google Scholar
  20. Liu Q, Jiang X, Xie S-P, Liu WT (2005) Sea surface wind and cold tongue over the winter South China Sea. IEEE Int 5:3294–3297Google Scholar
  21. Liu Q-Y, Wang D, Wang X, Shu Y, Xie Q, Chen J (2014) Thermal variations in the South China Sea associated with the eastern and central Pacific El Niño events and their mechanisms. J Geophys Res (Oceans) 119:8955–8972CrossRefGoogle Scholar
  22. Madhusoodanan MS, Thompson B (2011) Decadal variability of the Arctic Ocean thermal structure. Ocean Dyn 61:873–880CrossRefGoogle Scholar
  23. Price JF, Weller RA, Schudlich RR (1987) Wind-driven ocean currents and Ekman transport. Science 238:1534–1538CrossRefGoogle Scholar
  24. Qu T (2001) Role of ocean dynamics in determining the mean seasonal cycle of the South China Sea surface temperature. J Geophys Res 106:6943–6955CrossRefGoogle Scholar
  25. Qu T, Du Y, Strachan J, Meyers G, Slingo J (2005) Sea surface temperature and its variability in the Indonesian region. Oceanography 18(4):50–61CrossRefGoogle Scholar
  26. Reynolds RW, Smith MTM, Liu C, Chelton DB, Casey KS, Schlax MG (2007) Daily high-resolution-blended analyses for sea surface temperature. J Clim 20:5473–5496CrossRefGoogle Scholar
  27. Shen S, Lau K-M (1995) Biennial oscillation associated with the East Asian summer monsoon and tropical sea surface temperature. J Meteorol Soc Jpn 73:105–124Google Scholar
  28. Shenoi SSC, Shankar D, Shetye SR (2005) On the accuracy of the simple ocean data assimilation analysis for estimating heat budgets of the Near-Surface Arabian Sea and Bay of Bengal. J Phys Oceanogr 35:395–400CrossRefGoogle Scholar
  29. Stommel H (1965) The Gulf stream. University of Calif Press, Berkeley, p 248Google Scholar
  30. Thompson B, Tkalich P (2014) Mixed layer thermodynamics of the Southern South China Sea. Clim Dyn 43:2061–2075CrossRefGoogle Scholar
  31. Tomita T, Yasunari T (1996) Role of the northeast winter monsoon on the biennial oscillation of the ENSO/monsoon system. J Meteorol Soc Jpn 74:399–413Google Scholar
  32. Varikoden H, Samah AA, Babu CA (2010) The cold tongue in the South China Sea during boreal winter and its interaction with the atmosphere. Adv Atmos Sci 27(2):265–273CrossRefGoogle Scholar
  33. Vialard J, Delecluse P (1998) An OGCM study for the TOGA Decade. Part I: role of salinity in the physics of the Western Pacific Fresh Pool. J Phys Oceanogr 28:1071–1088CrossRefGoogle Scholar
  34. Wang C, Wang W, Wang D, Wang Q (2006) Interannual variability of the South China Sea associated with El Niño. J Geophys Res 111:C03023. doi:10.1029/2005JC003333 Google Scholar
  35. Wyrtki K (1961) Physical oceanography of Southeast Asian waters: scientific results of marine investigations of the South China Sea and Gulf of Thailand. Scripps Institution of Oceanography, NAGA Rep 2, La Jolla, p 195Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Bijoy Thompson
    • 1
  • Pavel Tkalich
    • 1
  • Paola Malanotte-Rizzoli
    • 2
  • Bastien Fricot
    • 3
  • Juliette Mas
    • 3
  1. 1.Tropical Marine Science InstituteNational University of SingaporeSingaporeSingapore
  2. 2.Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeUSA
  3. 3.French Naval AcademyBrestFrance

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