Climate Dynamics

, Volume 42, Issue 5–6, pp 1243–1258 | Cite as

Interannual and interdecadal variability of ocean temperature along the equatorial Pacific in conjunction with ENSO



In this paper, the leading modes of ocean temperature anomalies (OTA) along the equatorial Pacific Ocean are analyzed and their connection with El Niño-Southern Oscillation (ENSO) and interdecadal variation is investigated. The first two leading modes of OTA are connected with the different phases of the canonical ENSO and display asymmetric features of ENSO evolution. The third leading mode depicts a tripole pattern with opposite variation of OTA above the thermocline in the central Pacific to that along the thermocline in the eastern and western Pacific. This mode is found to be associated with so-called ENSO-Modoki. Insignificant correlations of this mode with the first two leading modes suggest that ENSO-Modoki may be a mode that is independent to the canonical ENSO and also has longer time scales compared with the canonical ENSO. The fourth mode reflects a warming (cooling) tendency above (below) the thermocline since 2000. Both the first and second modes have a large contribution to the interdecadal change in thermocline during 1979–2012. Also, the analysis also documents that both ENSO and OTA shifted into higher frequency since 2000 compared with that during 1979–1999. Interestingly, the ENSO-Modoki related OTA mode does not have any trend or significant interdecadal shift during 1979–2012. In addition, it is shown that first four EOF modes seem robust before and after 1999/2000, suggesting that the interdecadal shift of the climate system in the tropical Pacific is mainly a frequency shift and the changes in spatial pattern are relatively small, although the mean states over two periods experienced some significant changes.


ENSO Ocean temperature along the equatorial pacific Tilt mode Warm water volume mode ENSO-Modoki Interannual and interdecadal variations 



We thank the TAO Project Office of NOAA/PMEL for supplying the TAO data, and appreciate the constructive comments of two reviewers as well as Drs. Wanqiu Wang, Yan Xue, and Hui Wang.


  1. An S-I, Jin F–F (2001) Collective role of thermocline and zonal advective feedbacks in the ENSO mode. J Clim 14:3421–3432CrossRefGoogle Scholar
  2. Ashok K, Behera SK, Rao SA, Weng H, Yamagata T (2007) El Niño Modoki and its possible teleconnection. J Geophys Res 112:C11007. doi:10.1029/2006JC003798 CrossRefGoogle Scholar
  3. Barnett TP, Latif M, Kirk E, Roeckner E (1991) On ENSO physics. J Clim 4(5):487–515CrossRefGoogle Scholar
  4. Behringer DW, Xue Y (2004) Evaluation of the global ocean data assimilation system at NCEP: the Pacific Ocean. Preprints, eighth symposium on integrated observing and assimilation systems for atmosphere, oceans, and land surface, Seattle, WA, Amer. Meteor Soc, 2.3 [Available online at]
  5. Bjerknes J (1969) Atmospheric teleconnections from the equatorial Pacific. Mon Weather Rev 97:163–172CrossRefGoogle Scholar
  6. Burgers G, Stephenson DB (1999) The “normality” of El Niño. Geophys Res Lett 26:1027–1030CrossRefGoogle Scholar
  7. Clarke AJ, S Van Gorder, Colantuono G (2007) Wind stress curl and ENSO discharge/recharge in the equatorial Pacific. J Phys Ocean: 37(4):1077–1091Google Scholar
  8. Clarke AJ (2010) Analytical theory for the quasi-steady and low-frequency equatorial ocean response to wind forcing: the ‘tilt’ and ‘warm water volume’ modes. J Phys Ocean 40(1):121–137CrossRefGoogle Scholar
  9. Collins M et al (2010) The impact of global warming on the tropical Pacific Ocean and El Niño. Nat Geosci 3:391–397. doi:10.1038/ngeo868 CrossRefGoogle Scholar
  10. Dewitte B, Thual S, Yeh S-W, An S-I, Moon B-K, Giese BS (2009) Low-frequency variability of temperature in the vicinity of the equatorial Pacific thermocline in SODA: role of equatorial wave dynamics and ENSO asymmetry. J Clim 22:5783CrossRefGoogle Scholar
  11. Di Lorenzo et al (2010) Central Pacific El Niño and decadal change in the North Pacific Oscillation. Nat Geosci 3 (11). doi:10.1038/NGEO984
  12. Glantz MH (2000) Currents of change: impacts of El Niño and La Niña on climate and society. Cambridge, UK: Cambridge University Press, 266 pp. ISBN 052178672XGoogle Scholar
  13. Guilyardi E et al (2009) Understanding El Niño in ocean–atmosphere general circulation models: progress and challenges. Bull Am Meteor Soc 90:325–340CrossRefGoogle Scholar
  14. Hoerling MP, Kumar A (2002) Atmospheric response patterns associated with tropical forcing. J Clim 15:2184–2203CrossRefGoogle Scholar
  15. Horii T, Ueki I, Hanawa K (2012) Breakdown of ENSO predictors in the 2000s: decadal changes of recharge/discharge-SST phase relation and atmospheric intra seasonal forcing. Geophys Res Lett 39:L10707. doi:10.1029/2012GL051740 CrossRefGoogle Scholar
  16. Hu Z–Z, Kumar A, Jha B, Wang W, Huang B, Huang B (2012) An analysis of warm pool and cold tongue El Niños: air-sea coupling processes, global influences, and recent trends. Clim Dyn 38(9–10):2017–2035. doi:10.1007/s00382-011-1224-9 CrossRefGoogle Scholar
  17. Hu Z–Z, Kumar A, Ren H-L, Wang H, L’Heureux M, Jin F–F (2013a) Weakened interannual variability in the tropical Pacific Ocean since 2000. J Clim (in press)Google Scholar
  18. Hu Z–Z, A Kumar, Y Xue, B Jha (2013b) Why were some La Niñas followed by another La Niña? Clim Dyn (submitted)Google Scholar
  19. Huang B, Xue Y, Zhang D, Kumar A, McPhaden MJ (2010) The NCEP GODAS ocean analysis of the tropical Pacific mixed layer heat budget on seasonal to interannual time scales. J Clim 23(18):4901–4925CrossRefGoogle Scholar
  20. Jin F–F (1997a) An equatorial ocean recharge paradigm for ENSO. Part I: conceptual model. J Atmos Sci 54:811–829CrossRefGoogle Scholar
  21. Jin F–F (1997b) An equatorial ocean recharge paradigm for ENSO. Part II: a stripped-down coupled model. J Atmos Sci 54:830–847CrossRefGoogle Scholar
  22. Kanamitsu M et al (2002) NCEP-DOE AMIP-II reanalysis (R-2). Bull Am Meteor 83:1631–1643CrossRefGoogle Scholar
  23. Kao H-Y, Yu J-Y (2009) Contrasting eastern-Pacific and central-Pacific types of ENSO. J Clim 22:615–632CrossRefGoogle Scholar
  24. Kessler WS (2002) Is ENSO a cycle or a series of events? Geophys Res Lett 29(23):2125. doi:10.1029/2002GL015924 CrossRefGoogle Scholar
  25. Kim ST, Yu J-Y, Kumar A, Wang H (2012) Central-Pacific El Niño in the NCEP CFS model and its extratropical associations. Mon Weather Rev 140:1908–1923CrossRefGoogle Scholar
  26. Kug J-S, Jin F–F, An S-I (2009) Two types of El Niño events: cold tongue El Niño and warm pool El Niño. J Clim 22:1499–1515. doi:10.1175/2008JCLI2624.1 CrossRefGoogle Scholar
  27. Kug J-S, Choi J, An S-I, Jin F–F, Wittenberg AT (2010) Warm pool and cold tongue El Niño events as simulated by the GFDL 2.1 coupled GCM. J Clim 23:1226–1239CrossRefGoogle Scholar
  28. Kumar A, Zhang Q, Peng P, Jha B (2005) SST-forced atmospheric variability in an atmospheric general circulation model. J Clim 18:3953–3967CrossRefGoogle Scholar
  29. Kumar A, Chen M, Zhang L, Wang W, Xue Y, Wen W, Marx L, Huang B (2012) An analysis of the nonstationarity in the bias of sea surface temperature forecasts for the NCEP climate forecast system (CFS) version 2. Mon Weather Rev 140: 3003–3016.
  30. L’Heureux M, Collins D, Hu Z–Z (2013) Linear trends in sea surface temperature of the tropical Pacific Ocean and implications for the El Niño-Southern Oscillation. Clim Dyn 40(5–6):1223–1236. doi:10.1007/s00382-012-1331-2 Google Scholar
  31. McPhaden MJ (1993) TOGA-TAO and the 1991–93 El Niño Southern Oscillation event. Oceanography 6(2):36–44CrossRefGoogle Scholar
  32. McPhaden MJ (2012) A 21st century shift in the relationship between ENSO SST and warm water volume anomalies. Geophys Res Lett 39:L09706. doi:10.1029/2012GL051826 CrossRefGoogle Scholar
  33. McPhaden MJ, Lee T, McClurg D (2011) El Niño and its relationship to changing background conditions in the tropical Pacific Ocean. Geophys Res Lett 38:L15709. doi:10.1029/2011GL048275 CrossRefGoogle Scholar
  34. Meinen CS, McPhaden MJ (2000) Observations of warm water volume changes in the equatorial Pacific and their relationship to El Niño and La Niña. J Clim 13:3551–3559CrossRefGoogle Scholar
  35. Moon B-K et al (2004) Vertical structure variability in the equatorial Pacific before and after the Pacific climate shift of the 1970s. Geophys Res Lett 31(3):L03203. doi:10.1029/2003GL018829 CrossRefGoogle Scholar
  36. National Research Council (2010) Assessment of intraseasonal to interannual climate prediction and predictability. The National Academies Press: Washington, 192 pp. ISBN-10: 0-309-15183-XGoogle Scholar
  37. Neelin JD et al (1998) ENSO theory. J Geophys Res 103:14261–14290CrossRefGoogle Scholar
  38. Okumura YM, Deser C (2010) Asymmetry in the duration of El Niño and La Niña. J Clim 23:5826–5843CrossRefGoogle Scholar
  39. Okumura YM, Ohba M, Deser C, Ueda H (2011) A proposed mechanism for the asymmetric duration of El Niño and La Niña. J Clim 24:3822–3829. doi:10.1175/2011JCLI3999.1 CrossRefGoogle Scholar
  40. Philander SGH (1990) El Niño, La Niña and the Southern Oscillation. Academic Press, San Diego, 293 pp. ISBN 0125532350Google Scholar
  41. Picaut J, Ioualalen M, Menkes C, Delcroix T, McPhaden MJ (1996) Mechanism of the zonal displacements of the Pacific warm pool: implications for ENSO. Science 274:1486–1489CrossRefGoogle Scholar
  42. Ropelewski C, Halpert M (1987) Global and regional scale precipitation patterns associated with the El Niño-Southern Oscillation. Mon Weather Rev 115:1606–1626CrossRefGoogle Scholar
  43. Smith TM, Reynolds RW, Peterson TC, Lawrimore J (2008) Improvements to NOAA’s historical merged land-ocean surface temperature analysis (1880–2006). J Clim 21:2283–2296CrossRefGoogle Scholar
  44. Trenberth KE, Smith L (2006) The vertical structure of temperature in the tropics: different flavors of El Niño. J Clim 19:4956–4973CrossRefGoogle Scholar
  45. Vimont DJ, Alexander M, Fontaine A (2009) Mid-latitude excitation of tropical variability in the Pacific: the role of thermodynamic coupling and seasonality. J Clim 22:518–534CrossRefGoogle Scholar
  46. Wang C, Picaut J (2004) Understanding ENSO physics—a review. Earth’s climate: the ocean-atmosphere interaction. In: C Wang, S-P Xie, JA Carton (Eds.) AGU Geophys Monogr Ser, 147: 21–48Google Scholar
  47. Wang W, Chen M, Kumar A (2010) An assessment of the CFS real-time seasonal forecasts. Weather Forecast 25:950–969. doi:10.1175/2010WAF2222345.1 CrossRefGoogle Scholar
  48. Weare BC, Navato AR, Newell RE (1976) Empirical orthogonal analysis of Pacific sea surface temperatures. J Phys Ocean 6:671–678CrossRefGoogle Scholar
  49. Xue Y, Chen M, Kumar A, Hu Z–Z, Wang W (2013) Prediction skill and bias of tropical Pacific sea surface temperatures in the NCEP climate forecast system version 2. J Clim (in press)Google Scholar
  50. Yu J-Y, Kao H-Y, Lee T, Kim ST (2011) Subsurface ocean temperature indices for Central-Pacific and Eastern-Pacific types of El Niño and La Niña events. Theor Appl Clim 103(3–4):337–344. doi:10.1007/s00704-010-0307-6 CrossRefGoogle Scholar
  51. Zhang R-H, Levitus S (1996) Structure and evolution of interannual variability of the tropical Pacific upper ocean temperature. J Geophys Res 101:20501–20524CrossRefGoogle Scholar
  52. Zhang R-H, Levitus S (1997) Interannual variability of the coupled tropical Pacific ocean-atmosphere system associated with the El Nino/Southern Oscillation. J Clim 10:1312–1330CrossRefGoogle Scholar

Copyright information

© Springer-Verlag (outside the USA) 2013

Authors and Affiliations

  1. 1.Climate Prediction CenterNCEP/NWS/NOAACollege ParkUSA

Personalised recommendations