• Alexander, M. A., D. J. Vimont, P. Chang, and J. D. Scott, 2010: The impact of extratropical atmospheric variability on ENSO: Testing the seasonal footprinting mechanism using coupled model experiments. J. Climate, 23, 28852901.

    • Search Google Scholar
    • Export Citation
  • Bjerknes, J., 1969: Atmospheric teleconnections from the equatorial Pacific. Mon. Wea. Rev., 97, 163172.

  • Bunge, L., and A. J. Clarke, 2009: A verified estimation of the El Niño index Nino-3.4 since 1877. J. Climate, 22, 39793992.

  • Cane, M. A., 1979: The response of an equatorial ocean to simple wind-stress patterns. I: Model formulation and analytical results. J. Mar. Res., 37, 233252.

    • Search Google Scholar
    • Export Citation
  • Cane, M. A., A. C. Clement, A. Kaplan, Y. Kushnir, D. Pozdnyakov, R. Seager, S. E. Zebiak, and R. Murtugudde, 1997: Twentieth century sea surface temperature trends. Science, 275, 957960.

    • Search Google Scholar
    • Export Citation
  • Carton, J. A., and B. S. Giese, 2008: A reanalysis of ocean climate using Simple Ocean Data Assimilation (SODA). Mon. Wea. Rev., 136, 29993017.

    • Search Google Scholar
    • Export Citation
  • Chang, P., 1994: A study of the seasonal cycle of sea surface temperature in the tropical Pacific Ocean using reduced gravity models. J. Geophys. Res., 99 (C4), 77257741.

    • Search Google Scholar
    • Export Citation
  • Chang, P., L. Zhang, R. Saravanan, D. J. Vimont, J. C. H. Chiang, L. Ji, H. Seidel, and M. K. Tippett, 2007: Pacific meridional mode and El Niño–Southern Oscillation. Geophys. Res. Lett., 34, L16608, doi:10.1029/2007GL030302.

    • Search Google Scholar
    • Export Citation
  • Chiang, J. C. H., Y. Fang, and P. Chang, 2008: Interhemispheric thermal gradient and tropical Pacific climate. Geophys. Res. Lett., 35, L14704, doi:10.1029/2008GL034166.

    • Search Google Scholar
    • Export Citation
  • Clement, A. C., R. Seager, M. A. Cane, and S. E. Zebiak, 1996: An ocean dynamical thermostat. J. Climate, 9, 21902196.

  • Collins, M., and Coauthors, 2005: El Niño– or La Niña–like climate change? Climate Dyn., 24, 89104.

  • Collins, M., and Coauthors, 2010: The impact of global warming on the tropical Pacific Ocean and El Niño. Nat. Geosci., 3, 391397.

  • Collins, W. D., and Coauthors, 2006a: The formulation and atmospheric simulation of the Community Atmospheric Model: CAM3. J. Climate, 19, 21442161.

    • Search Google Scholar
    • Export Citation
  • Collins, W. D., and Coauthors, 2006b: The Community Climate System Model, version 3 (CCSM3). J. Climate, 19, 21222143.

  • Derber, J., and A. Rosati, 1989: A global oceanic data assimilation system. J. Phys. Oceanogr., 19, 13331347.

  • de Szoeke, S. P., S.-P. Xie, T. Miyama, K. J. Richards, and R. J. O. Small, 2007: What maintains the SST front north of the equatorial cold tongue? J. Climate, 20, 25002514.

    • Search Google Scholar
    • Export Citation
  • Deser, C., A. S. Phillips, and M. A. Alexander, 2010: Twentieth century tropical sea surface temperature trends revisited. Geophys. Res. Lett., 37, L10701, doi:10.1029/2010GL043321.

    • Search Google Scholar
    • Export Citation
  • DiNezio, P., A. Clement, G. A. Vecchi, B. J. Soden, B. Kirtman, and S.-K. Lee, 2009: Climate response of the equatorial Pacific to global warming. J. Climate, 22, 48734892.

    • Search Google Scholar
    • Export Citation
  • Du, Y., and S.-P. Xie, 2008: Role of atmospheric adjustments in the tropical Indian Ocean warming during the 20th century in climate models. Geophys. Res. Lett., 35, L08712, doi:10.1029/2008GL033631.

    • Search Google Scholar
    • Export Citation
  • Fang, Y., 2005: A coupled model study of the remote influence of ENSO on tropical Atlantic SST variability. Ph.D. thesis, Texas A&M University, 93 pp.

  • Fang, Y., J. C. H. Chiang, and P. Chang, 2008: Variation of mean sea surface temperature and modulation of El Niño–Southern Oscillation variance during the past 150 years. Geophys. Res. Lett., 35, L08703, doi:10.1029/2007GL033097.

    • Search Google Scholar
    • Export Citation
  • Frankignoul, C., 1985: Sea surface temperature anomalies, planetary waves and air–sea feedback in the middle latitudes. Rev. Geophys., 23, 357390.

    • Search Google Scholar
    • Export Citation
  • Giese, B. S., and S. Ray, 2011: El Niño variability in simple ocean data assimilation (SODA), 1871–2008. J. Geophys. Res., 116, C02024, doi:10.1029/2010JC006695.

    • Search Google Scholar
    • Export Citation
  • Gill, A., 1980: Some simple solutions for heat-induced tropical circulation. Quart. J. Roy. Meteor. Soc., 106, 447462.

  • Held, I. M., and B. J. Soden, 2006: Robust responses of the hydrological cycle to global warming. J. Climate, 19, 56865699.

  • Jacob, R. L., 1997: Low frequency variability in a simulated atmosphere ocean system. Ph.D. thesis, University of Wisconsin—Madison, 155 pp.

  • Jin, F.-F., 1996: Tropical ocean–atmosphere interaction, the Pacific cold tongue, and the El Niño–Southern Oscillation. Science, 274, 7678.

    • Search Google Scholar
    • Export Citation
  • Karnauskas, K., R. Seager, A. Kaplan, Y. Kushnir, and M. Cane, 2009: Observed strengthening of the zonal sea surface temperature gradient across the equatorial Pacific Ocean. J. Climate, 22, 43164321.

    • Search Google Scholar
    • Export Citation
  • Kessler, W. S., 2006: The circulation of the eastern tropical Pacific: A review. Prog. Oceanogr., 69, 181217.

  • Liu, Z., J. Kutzbach, and L. Wu, 2000: Modeling climatic shift of El Niño variability in the Holocene. Geophys. Res. Lett., 27, 22652268.

    • Search Google Scholar
    • Export Citation
  • Liu, Z., S. J. Vavrus, F. He, N. Wen, and Y. Zhang, 2005: Rethinking tropical ocean response to global warming: The enhanced equatorial warming. J. Climate, 18, 46844700.

    • Search Google Scholar
    • Export Citation
  • Meehl, G. A., and W. M. Washington, 1996: El Niño–like climate change in a model with increased atmospheric CO2 concentrations. Nature, 382, 5660.

    • Search Google Scholar
    • Export Citation
  • Meehl, G. A., W. D. Collins, B. A. Boville, J. T. Kiehl, T. M. L. Wigley, and J. M. Arblaster, 2000: Response of the NCAR Climate System Model to increased CO2 and the role of physical processes. J. Climate, 13, 18791898.

    • Search Google Scholar
    • Export Citation
  • Meehl, G. A., and Coauthors, 2006: Climate change projections for the twenty-first century and climate change commitment in the CCSM3. J. Climate, 19, 25972616.

    • Search Google Scholar
    • Export Citation
  • Meehl, G. A., and Coauthors, 2007: Global climate projections. Climate Change 2007: The Physical Science Basis, S. Solomon et al., Eds., Cambridge University Press, 747–845.

  • Monterey, G. I., and S. Levitus, 1997: Climatological cycle of mixed layer depth in the World Ocean. NOAA/NESDIS Atlas 14, 5 pp.

  • Richter, I., and S.-P. Xie, 2008: The muted precipitation increase in global warming simulations: A surface evaporation perspective. J. Geophys. Res., 113, D24118, doi:10.1029/2008JD010561.

    • Search Google Scholar
    • Export Citation
  • Schubert, S. D., 2004: On the cause of the 1930s Dust Bowl. Science, 303, 18551859.

  • Seager, R., S. E. Zebiak, and M. A. Cane, 1988: A model of the tropical Pacific sea surface temperature climatology. J. Geophys. Res., 93, 12651280.

    • Search Google Scholar
    • Export Citation
  • Smith, T. M., R. W. Reynolds, R. E. Livezey, and D. C. Stokes, 1996: Reconstruction of historical sea surface temperatures using empirical orthogonal functions. J. Climate, 9, 14031420.

    • Search Google Scholar
    • Export Citation
  • Taylor, K. E., R. J. Stouffer, and G. A. Meehl, 2012: An overview of CMIP5 and the experiment design. Bull. Amer. Meteor. Soc., 93, 485498.

    • Search Google Scholar
    • Export Citation
  • Timmermann, A., J. Oberhuber, A. Bacher, M. Esch, M. Latif, and E. Roeckner, 1999: Increased El Niño frequency in a climate model forced by future greenhouse warming. Nature, 398, 694696.

    • Search Google Scholar
    • Export Citation
  • Timmermann, A., F.-F. Jin, and M. Collins, 2004: Intensification of the annual cycle in the tropical Pacific due to greenhouse warming. Geophys. Res. Lett., 31, L12208, doi:10.1029/2004GL019442.

    • Search Google Scholar
    • Export Citation
  • Tokinaga, H., S.-P. Xie, C. Deser, Y. Kosaka, and Y. M. Okumura, 2012: Slowdown of the Walker circulation driven by tropical Indo-Pacific warming. Nature, 491, 439443.

    • Search Google Scholar
    • Export Citation
  • Vecchi, G. A., and B. J. Soden, 2007a: Effect of remote sea surface temperature change on tropical cyclone potential intensity. Nature, 450, 10661070, doi:10.1038/nature06423.

    • Search Google Scholar
    • Export Citation
  • Vecchi, G. A., and B. J. Soden, 2007b: Global warming and the weakening of the tropical circulation. J. Climate, 20, 43164340.

  • Vecchi, G. A., B. J. Soden, A. T. Wittenberg, I. M. Held, A. Leetmaa, and M. J. Harrison, 2006: Weakening of tropical Pacific atmospheric circulation due to anthropogenic forcing. Nature, 441, 7376, doi:10.1038/nature04744.

    • Search Google Scholar
    • Export Citation
  • Vecchi, G. A., A. Clement, and B. J. Soden, 2008a: Examining the tropical Pacific’s response to global warming. Eos, Trans. Amer. Geophys. Union, 89, 9, doi:10.1029/2008EO090002.

    • Search Google Scholar
    • Export Citation
  • Vecchi, G. A., K. L. Swanson, and B. J. Soden, 2008b: Whither hurricane activity? Science, 322, 687689.

  • Wang, C., and J. Picaut, 2004: Understanding ENSO Physics—A review. Earth Climate: The Ocean–Atmosphere Interaction, Geophys. Monogr., Vol. 147, Amer. Geophys. Union, 21–48.

  • Wang, C., and S.-K. Lee, 2008: Global warming and United States landfalling hurricanes. J. Geophys. Res., 35, L02708, doi:10.1029/2007GL032396.

    • Search Google Scholar
    • Export Citation
  • Woodruff, S. D., and Coauthors, 2011: ICOADS release 2.5: Extensions and enhancements to the surface marine meteorological archive. Int. J. Climatol., 31, 951967.

    • Search Google Scholar
    • Export Citation
  • Xie, S.-P., 1994: On the genesis of the equatorial annual cycle. J. Climate, 7, 20082013.

  • Xie, S.-P., 1995: Interaction between the annual and interannual variations in the equatorial Pacific. J. Phys. Oceanogr., 25, 19301941.

    • Search Google Scholar
    • Export Citation
  • Xie, S.-P., 1996: Westward propagation of latitudinal asymmetry in a coupled ocean–atmosphere model. J. Atmos. Sci., 53, 32363250.

  • Xie, S.-P., and S. G. H. Philander, 1994: A coupled ocean-atmosphere model of relevance to the ITCZ in the eastern Pacific. Tellus, 46A, 340350.

    • Search Google Scholar
    • Export Citation
  • Xie, S.-P., C. Deser, G. A. Vecchi, J. Ma, H. Teng, and A. T. Wittenberg, 2010: Global warming pattern formation: Sea surface temperature and rainfall. J. Climate, 23, 966986.

    • Search Google Scholar
    • Export Citation
  • Yeh, S.-W., Y.-G. Ham, and J.-Y. Lee, 2012: Changes in the tropical Pacific SST trend from CMIP3 to CMIP5 and its implication of ENSO. J. Climate, 25, 77647771.

    • Search Google Scholar
    • Export Citation
  • Zebiak, S. E., and M. A. Cane, 1987: A model ENSO. Mon. Wea. Rev., 115, 22622278.

  • Zhang, L., and L. Wu, 2012: Can oceanic freshwater flux amplify global warming? J. Climate, 25, 34173430.

  • Zhang, L., P. Chang, and L. Ji, 2009: Linking the Pacific meridional mode to ENSO: Coupled model analysis. J. Climate, 22, 34883505.

  • Zhang, L., L. Wu, and L. Yu, 2011: Oceanic origin of a recent La Niña–like trend in the tropical Pacific. Adv. Atmos. Sci., 28, 11091117.

    • Search Google Scholar
    • Export Citation
  • Zhang, M., and H. Song, 2006: Evidence of deceleration of atmospheric vertical overturning circulation over the tropical Pacific. Geophys. Res. Lett., 33, L12701, doi:10.1029/2006GL025942.

    • Search Google Scholar
    • Export Citation
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A Study of Response of the Equatorial Pacific SST to Doubled-CO2 Forcing in the Coupled CAM–1.5-Layer Reduced-Gravity Ocean Model

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  • 1 Physical Oceanography Laboratory, Ocean University of China, Qindao, China
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Abstract

The response of the equatorial Pacific SST under CO2 doubling is investigated using Community Atmosphere Model, version 3.1 (CAM3.1)–1.5-layer reduced-gravity ocean (RGO) coupled model. A robust El Niño–like warming pattern is found in the equatorial Pacific. The surface heat budget analyses suggest the El Niño–like pattern results from a weakening of the Walker circulation. In the western equatorial Pacific, all the heat flux components are important to warm the ocean, with the vast majority canceled by entraiment cooling related to increased stratification. In the central-eastern Pacific, the oceanic horizontal advections along with longwave radiation and latent heat flux act to warm the ocean, with entrainment, shortwave radiation, and horizontal diffusion acting as damping terms. An enhanced annual cycle of SST in the equatorial Pacific is also found, which is driven by the ocean dynamical adjustments to changing winds in the eastern ocean.

Although the ocean model used here is a simple reduced-gravity model, the El Niño–like response supports the results of some full ocean–atmosphere general circulation models (GCMs) performed for the World Climate Research Programme (WCRP) Coupled Model Intercomparison Project (CMIP) phase-5, indicating that the CAM3.1–RGO model can be taken as a useful and efficient tool to study equatorial Pacific response under changing climate.

Corresponding author address: Fan Jia, Physical Oceanography Laboratory, Ocean University of China, 238 Songling Road, Qingdao 266100, China. E-mail: afanayang31@163.com

Abstract

The response of the equatorial Pacific SST under CO2 doubling is investigated using Community Atmosphere Model, version 3.1 (CAM3.1)–1.5-layer reduced-gravity ocean (RGO) coupled model. A robust El Niño–like warming pattern is found in the equatorial Pacific. The surface heat budget analyses suggest the El Niño–like pattern results from a weakening of the Walker circulation. In the western equatorial Pacific, all the heat flux components are important to warm the ocean, with the vast majority canceled by entraiment cooling related to increased stratification. In the central-eastern Pacific, the oceanic horizontal advections along with longwave radiation and latent heat flux act to warm the ocean, with entrainment, shortwave radiation, and horizontal diffusion acting as damping terms. An enhanced annual cycle of SST in the equatorial Pacific is also found, which is driven by the ocean dynamical adjustments to changing winds in the eastern ocean.

Although the ocean model used here is a simple reduced-gravity model, the El Niño–like response supports the results of some full ocean–atmosphere general circulation models (GCMs) performed for the World Climate Research Programme (WCRP) Coupled Model Intercomparison Project (CMIP) phase-5, indicating that the CAM3.1–RGO model can be taken as a useful and efficient tool to study equatorial Pacific response under changing climate.

Corresponding author address: Fan Jia, Physical Oceanography Laboratory, Ocean University of China, 238 Songling Road, Qingdao 266100, China. E-mail: afanayang31@163.com
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