Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

The impact of global warming on the tropical Pacific Ocean and El Niño

Subjects

Abstract

The El Niño–Southern Oscillation (ENSO) is a naturally occurring fluctuation that originates in the tropical Pacific region and affects ecosystems, agriculture, freshwater supplies, hurricanes and other severe weather events worldwide. Under the influence of global warming, the mean climate of the Pacific region will probably undergo significant changes. The tropical easterly trade winds are expected to weaken; surface ocean temperatures are expected to warm fastest near the equator and more slowly farther away; the equatorial thermocline that marks the transition between the wind-mixed upper ocean and deeper layers is expected to shoal; and the temperature gradients across the thermocline are expected to become steeper. Year-to-year ENSO variability is controlled by a delicate balance of amplifying and damping feedbacks, and one or more of the physical processes that are responsible for determining the characteristics of ENSO will probably be modified by climate change. Therefore, despite considerable progress in our understanding of the impact of climate change on many of the processes that contribute to El Niño variability, it is not yet possible to say whether ENSO activity will be enhanced or damped, or if the frequency of events will change.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Changes in global and tropical Pacific mean climate from complex climate models as a function of the global mean temperature change.
Figure 2: Idealized schematic showing atmospheric and oceanic conditions of the tropical Pacific region and their interactions during normal conditions, El Niño conditions, and in a warmer world.
Figure 3: Projected changes in the amplitude of ENSO variability, as a response to global warming, from the CMIP3 models8,9.

References

  1. Vecchi, G. A. & Wittenberg, A. T. El Niño and our future climate: Where do we stand? Wiley Interdisciplinary Reviews: Climate Change (in the press).

  2. Fedorov, A. V. Estimating net energy dissipation rates in the tropical ocean: diabatic effects on ENSO dynamics. J. Climate 20, 1099–1108 (2007).

    Article  Google Scholar 

  3. Roberts, W. G. H. & Battisti, D. S. A new tool for evaluating the physics of coupled atmosphere-ocean variability in nature and in General Circulation Models. Clim. Dynam. (in the press).

  4. Philip, S. & van Oldenborgh, G. J. Significant atmospheric nonlinearities in the ENSO cycle. J. Climate 22, 4014–4028 (2009).

    Article  Google Scholar 

  5. Philip, S. Y. & van Oldenborgh, G. J. Atmospheric properties and ENSO: models versus observations. Clim. Dynam. 10.1007/s00382-009-0579-7 (in the press).

  6. Guilyardi, E. et al. Understanding El Niño in ocean–atmosphere General Circulation Models: progress and challenges. Bull. Am. Meteorol. Soc. 90, 325–340 (2009).

    Article  Google Scholar 

  7. McPhaden, M. J. & Zhang, X. B. Asymmetry in zonal phase propagation of ENSO sea surface temperature anomalies. Geophys. Res. Lett. 36, L13703 (2009).

    Article  Google Scholar 

  8. Meehl, G. A. et al. The WCRP CMIP3 multimodel dataset: A new era in climate change research. Bull. Am. Meteorol. Soc. 88, 1383–1394 (2007).

    Article  Google Scholar 

  9. van Oldenborgh, G. J., Philip, S. & Collins, M. El Niño in a changing climate: a multi-model study. Ocean Sci. 2, 267–298 (2005).

    Google Scholar 

  10. Guilyardi, E. El Niño mean state seasonal cycle interactions in a multi-model ensemble. Clim. Dynam. 26, 329–348 (2006).

    Article  Google Scholar 

  11. AchutaRao, K. & Sperber, K. ENSO simulations in coupled ocean-atmosphere models: are the current models better? Clim. Dynam. 27, 1–15 (2006).

    Article  Google Scholar 

  12. Merryfield, W. J. Changes to ENSO under CO2 doubling in a multimodel ensemble. J. Climate 19, 4009–4027 (2006).

    Article  Google Scholar 

  13. Capotondi, A., Wittenberg, A. & Masina, S. Spatial and temporal structure of tropical Pacific interannual variability in 20th century coupled simulations. Ocean Model. 15, 274–298 (2006).

    Article  Google Scholar 

  14. Lengaigne, M. & Vecchi, G. A. Contrasting the termination of moderate and extreme El Niño events in Coupled General Circulation Models. Clim. Dynam. 10.1007/s00382-009-0562-3 (in the press).

  15. Philip, S. Y. & van Oldenborgh, G. J. Shifts in ENSO coupling processes under global warming. Geophys. Res. Letts. 33, L11704 (2006).

    Article  Google Scholar 

  16. Jin, F.-F., Kim, S. T. & Bejarano, L. A coupled-stability index for ENSO. Geophys. Res. Lett. 33, L23708 (2006).

    Article  Google Scholar 

  17. Lloyd, J., Guilyardi, E., Weller, H. & Slingo, J. The role of atmosphere feedbacks during ENSO in the CMIP3 models. Atmos. Sci. Lett. 10, 170–176 (2009).

    Article  Google Scholar 

  18. Jin, F-F., An, S-I., Timmermann, A. & Zhao, J. Strong El Nino events and nonlinear dynamical heating. Geophys. Res. Lett. 30, 1120 (2003).

    Article  Google Scholar 

  19. An, S-I. A review of interdecadal changes in the nonlinearity of the El Nino-Southern Oscillation. Theor. Appl. Climatol. 97, 29–40 (2009).

    Article  Google Scholar 

  20. Pezzulli, S., Stephenson, D. & Hannachi, A. The variability of seasonality. J. Climate 18, 71–88 (2005).

    Article  Google Scholar 

  21. Yang, H. & Zhang, Q. Anatomizing the ocean's role in ENSO changes under global warming. J. Climate 21, 6539–6555 (2008).

    Article  Google Scholar 

  22. An, S. I., Kug, J. S., Ham, Y. G. & Kang, I. S. Successive modulation of ENSO to the future greenhouse warming. J. Climate 21, 3–21 (2008).

    Article  Google Scholar 

  23. Held, I. M. & Soden, B. J. Robust responses of the hydrological cycle to global warming. J. Climate 19, 5686–5699 (2006).

    Article  Google Scholar 

  24. Vecchi, G. A. et al. Weakening of tropical Pacific atmospheric circulation due to anthropogenic forcing. Nature 441, 73–76 (2006).

    Article  Google Scholar 

  25. Vecchi, G. A. & Soden, B. J. Global warming and the weakening of the tropical circulation. J. Climate 20, 4316–4340 (2007).

    Article  Google Scholar 

  26. Power, S. B. & Smith, I. N. Weakening of the Walker circulation and apparent dominance of El Niño both reach record levels, but has ENSO really changed? Geophys. Res. Lett. 34, L18702 (2007).

    Article  Google Scholar 

  27. Zhang, M. & Song, H. Evidence of deceleration of atmospheric vertical overturning circulation over the tropical Pacific. Geophys. Res. Lett. 33, L12701 (2006).

    Article  Google Scholar 

  28. Bunge, L. & Clarke, A. J. A verified estimation of the El Niño index Niño-3.4 since 1877. J. Climate 22, 3979–3992 (2009).

    Article  Google Scholar 

  29. Karnauskas, K. B., Seager, R., Kaplan, A., Kushnir, Y. & Cane, M. A. Observed strengthening of the zonal sea surface temperature gradient across the equatorial Pacific Ocean. J. Climate 22, 4316–4321 (2009).

    Article  Google Scholar 

  30. DiNezio, P. N. et al. Climate response of the equatorial Pacific to global warming. J. Climate 22, 4873–4892 (2009).

    Article  Google Scholar 

  31. Yeh, S-W. et al. El Nino in a changing climate. Nature 461, 511–514 (2009).

    Article  Google Scholar 

  32. Zhang, Q., Guan, Y. & Yang, H. ENSO amplitude change in observation and coupled models. Adv. Atmos. Sci. 25, 361–366 (2008).

    Article  Google Scholar 

  33. An, S-I. Interannual variations of the tropical ocean instability wave and ENSO. J. Climate 21, 3680–3686 (2008).

    Article  Google Scholar 

  34. DiNezio, P., Clement, A. & Vecchi, G. A. Reconciling Differing Views of Tropical Pacific Climate Change. EOS, Trans. Amer. Geophys. Union 91, 141–152 (2010).

    Article  Google Scholar 

  35. Collins, M. et al. El Nino- or La Nina-like climate change? Clim. Dynam. 24, 89–104 (2005).

    Article  Google Scholar 

  36. Liu, Z., Vavrus, S., He, F., Wen, N. & Zhong, Y. Rethinking tropical ocean response to global warming: The enhanced equatorial warming. J. Climate 18, 4684–4700 (2005).

    Article  Google Scholar 

  37. Xie, S. P. et al. Global warming pattern formation: Sea surface temperature and rainfall. J. Climate 23, 966–986 (2010).

    Article  Google Scholar 

  38. Gastineau, G., Li, L. & Le Treut, H. The Hadley and Walker circulation changes in global warming conditions described by idealised atmospheric simulations. J. Climate 22, 3993–4013 (2009).

    Article  Google Scholar 

  39. Lin, J-L. The double-ITCZ problem in IPCC AR4 coupled GCMs: Ocean–atmosphere feedback analysis. J. Climate 20, 4497–4525 (2007).

    Article  Google Scholar 

  40. Inness, P. M. & Slingo, J. M. Simulation of the Madden-Julian Oscillation in a coupled general circulation model I: Comparison with observations and an atmosphere-only GCM. J. Climate 16, 345–364 (2003).

    Article  Google Scholar 

  41. Lin, J. L. et al. Tropical intraseasonal variability in 14 IPCC AR4 climate models. Part I: Convective signals. J. Climate 19, 2665–2690 (2006).

    Article  Google Scholar 

  42. Cobb, K., Charles, C. D., Cheng, H. & Edwards, R. L. El Niño-Southern Oscillation and tropical Pacific climate during the last millenium. Nature 424, 271–276 (2003).

    Article  Google Scholar 

  43. Tudhope, A. W. et al. Variability in the El Niño-Southern Oscillation through a glacial-interglacial cycle. Science 291, 1511–1517 (2001).

    Article  Google Scholar 

  44. D'Arrigo, R., Cook, E., Wilson, R., Allan, R. & Mann, M. On the variability of ENSO over the past six centuries. Geophys. Res. Lett. 32, L03711 (2005).

    Google Scholar 

  45. Rosenthal, Y. & Broccoli, A. J. In search of paleo-ENSO. Science 304, 219–221 (2004).

    Article  Google Scholar 

  46. Brown, J., Collins, M., Tudhope, A. W. & Toniazzo, T. Modelling mid-Holocene tropical climate and ENSO variability: Towards constraining predictions of future climate change with palaeo-data. Clim. Dynam. 30, 19–36 (2008).

    Article  Google Scholar 

  47. Timmermann, A., Lorenz, S., An, S. I., Clement, A. & Xie, S-P. The effect of orbital forcing on the mean climate and variability of the tropical Pacific. J. Climate 20, 4147–4159 (2007).

    Article  Google Scholar 

  48. Otto-Bliesner et al. A comparison of PMIP2 model simulations and the MARGO proxy reconstruction for tropical sea surface temperatures at last glacial maximum. Clim. Dynam. 32, 799–815 (2009).

    Article  Google Scholar 

  49. Crowley, T. Causes of climate change over the past 1000 years. Science 289, 270–277 (2000).

    Article  Google Scholar 

  50. Mann, M., Cane, M., Zebiak, S. & Clement, A. Volcanic and solar forcing of the tropical pacific over the past 1000 years. J. Climate 18, 417–456 (2005).

    Google Scholar 

  51. Emile-Geay, J., Seager, R., Cane, M. A., Cook, E. C. & Haug, G. H. Volcanoes and ENSO over the past millennium. J. Climate 21, 3134–3148 (2008).

    Article  Google Scholar 

  52. Wittenberg, A. T. Are historical records sufficient to constrain ENSO simulations? Geophys. Res. Lett. 36, L12702 (2009).

    Article  Google Scholar 

  53. Power, S., Haylock, M., Colman, R. & Wang, X. The predictability of interdecadal changes in ENSO and ENSO teleconnections. J. Climate 8, 2161–2180 (2006).

    Article  Google Scholar 

  54. Power, S. B. & Colman, R. Multi-year predictability in a coupled general circulation model. Clim. Dynam. 26, 247–272 (2006).

    Article  Google Scholar 

  55. Zelle, H. et al. El Nino and greenhouse warming: Results from ensemble simulations with the NCAR CCSM. J. Climate 18, 4669–4683 (2005).

    Article  Google Scholar 

  56. Meehl, G. A., Teng, H. & Branstator, G. Future changes of El Niño in two global coupled climate models. Clim. Dynam. 26, 549–566 (2006).

    Article  Google Scholar 

  57. Yeh, S. W., Park, Y. G. & Kirtman, B. P. ENSO amplitude changes in climate change commitment to atmospheric CO2 doubling. Geophys. Res. Lett. 33, L13711 (2006).

    Article  Google Scholar 

  58. Yeh, S. W. & Kirtman, B. P. ENSO amplitude changes due to climate change projections in different coupled models. J. Climate 20, 203–217 (2007).

    Article  Google Scholar 

  59. Cherchi, A., Masina, S. & Navarra, A. Impact of extreme CO2 levels on tropical climate: a CGCM study. Clim. Dynam. 31, 743–758 (2008).

    Article  Google Scholar 

  60. Park, W. et al. Tropical Pacific climate and its response to global warming in the Kiel climate model. J. Climate 22, 71–92 (2009).

    Article  Google Scholar 

  61. Guilyardi, E. et al. Atmosphere feedbacks during ENSO in a coupled GCM with a modified atmospheric convection scheme. J. Climate 22, 5698–5718 (2009).

    Article  Google Scholar 

  62. Bony, S. & Dufresne, J. L. Marine boundary layer clouds at the heart of tropical cloud feedback uncertainties in climate models. Geophys. Res. Lett. 32, L20806 (2005).

    Article  Google Scholar 

  63. Lengaigne, M. et al. Triggering of El Nino by westerly wind events. Clim. Dynam. 23, 601–620 (2004).

    Article  Google Scholar 

  64. Vecchi, G. A., Wittenberg, A. T. & Rosati, A. Reassessing the role of stochastic forcing in the 1997–8 El Niño. Geophys. Res. Lett. 33, L01706 (2006).

    Article  Google Scholar 

  65. Gebbie, G., Eisenman, I., Wittenberg, A. & Tziperman, E. Modulation of westerly wind bursts by sea surface temperature: A semistochastic feedback for ENSO. J. Atmos. Sci. 64, 3281–3295 (2007).

    Article  Google Scholar 

  66. Zavala-Garay, J. et al. Sensitivity of hybrid ENSO models to unresolved atmospheric variability. J. Climate 21, 3704–3721 (2008).

    Article  Google Scholar 

  67. Maes, C., Picaut, J. & Belamari, S. Salinity barrier layer and onset of El Nino in a Pacific coupled model. Geophs. Res. Lett. 29, 2206 (2002).

    Article  Google Scholar 

  68. Zhang, R-H. & Busalacchi, A. J. Freshwater flux (FWF)-induced oceanic feedback in a hybrid coupled model of the tropical Pacific. J. Climate 22, 853–879 (2009).

    Article  Google Scholar 

  69. Yu, J. Y. & Liu, W. T. A linear relationship between ENSO intensity and tropical instability wave activity in the eastern Pacific Ocean. Geophys. Res. Lett. 30, L1735 (2003).

    Article  Google Scholar 

  70. Seo, H., Jochum, M., Murtugudde, R., Miller, A. J. & Roads, J. O. Feedback of tropical instability-wave-induced atmospheric variability onto the ocean. J. Climate 20, 5842–5855 (2007).

    Article  Google Scholar 

  71. Roberts, M. J. et al. Impact of resolution on the tropical Pacific circulation in a matrix of coupled models. J. Climate 22, 2541–2556 (2009).

    Article  Google Scholar 

  72. Collins, M. et al. A comparison of perturbed physics and multi-model ensembles: Model errors, feedbacks and forcings. Clim. Dynam. 10.1007/s00382-010-0808-0 (in the press).

Download references

Acknowledgements

The authors prepared this Review on behalf of the Climate Variability and Predictability (CLIVAR) Pacific Panel.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mat Collins.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Collins, M., An, SI., Cai, W. et al. The impact of global warming on the tropical Pacific Ocean and El Niño. Nature Geosci 3, 391–397 (2010). https://doi.org/10.1038/ngeo868

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ngeo868

Further reading

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing