Editorial Type:
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Article Type:
Research Article

Impact of East Asian Winter and Australian Summer Monsoons on the Enhanced Surface Westerlies over the Western Tropical Pacific Ocean Preceding the El Niño Onset

Yangxing Zheng Center for Ocean–Atmospheric Prediction Studies, The Florida State University, Tallahassee, Florida

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Renhe Zhang State Key Laboratory of Severe Weather (LaSW), Chinese Academy of Meteorological Sciences, Beijing, China

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Mark A. Bourassa Center for Ocean–Atmospheric Prediction Studies, and Department of Earth, Ocean and Atmospheric Science, The Florida State University, Tallahassee, Florida

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Print Publication:
01 Mar 2014
DOI:
https://doi.org/10.1175/JCLI-D-13-00369.1
Page(s):
1928–1944
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Abstract

Composite analysis from NCEP–NCAR reanalysis datasets over the period 1948–2007 indicates that stronger East Asian winter monsoons (EAWM) and stronger Australian summer monsoons (ASM) generally coexist in boreal winters preceding the onset of El Niño, although the EAWM tend to be weak after 1990, probably because of the decadal shift of EAWM and the change in El Niño events from cold-tongue type to warm-pool type. The anomalous EAWM and ASM enhance surface westerlies over the western tropical Pacific Ocean (WTP). It is proposed that the enhanced surface westerlies over the WTP prior to El Niño onset are generally associated with the concurrent anomalous EAWM and ASM. A simple analytical atmospheric model is constructed to test the hypothesis that the emergence of enhanced surface westerlies over the WTP can be linked to concurrent EAWM and ASM anomalies. Model results indicate that, when anomalous northerlies from the EAWM converge with anomalous southerlies from the ASM, westerly anomalies over the WTP are enhanced. This result provides a possible explanation of the co-impact of the EAWM and the ASM on the onset of El Niño through enhancing the surface westerly over the WTP.

Corresponding author address: Yangxing Zheng, Center for Ocean–Atmospheric Prediction Studies, The Florida State University, 2000 Levy Avenue, Room 238, Building A, Tallahassee, FL 32306. E-mail: yzheng@fsu.edu

Abstract

Composite analysis from NCEP–NCAR reanalysis datasets over the period 1948–2007 indicates that stronger East Asian winter monsoons (EAWM) and stronger Australian summer monsoons (ASM) generally coexist in boreal winters preceding the onset of El Niño, although the EAWM tend to be weak after 1990, probably because of the decadal shift of EAWM and the change in El Niño events from cold-tongue type to warm-pool type. The anomalous EAWM and ASM enhance surface westerlies over the western tropical Pacific Ocean (WTP). It is proposed that the enhanced surface westerlies over the WTP prior to El Niño onset are generally associated with the concurrent anomalous EAWM and ASM. A simple analytical atmospheric model is constructed to test the hypothesis that the emergence of enhanced surface westerlies over the WTP can be linked to concurrent EAWM and ASM anomalies. Model results indicate that, when anomalous northerlies from the EAWM converge with anomalous southerlies from the ASM, westerly anomalies over the WTP are enhanced. This result provides a possible explanation of the co-impact of the EAWM and the ASM on the onset of El Niño through enhancing the surface westerly over the WTP.

Corresponding author address: Yangxing Zheng, Center for Ocean–Atmospheric Prediction Studies, The Florida State University, 2000 Levy Avenue, Room 238, Building A, Tallahassee, FL 32306. E-mail: yzheng@fsu.edu
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  • Ashok, K., S. K. Behera, S. A. Rao, H. Weng, and T. Yamagata, 2007: El Niño Modoki and its possible teleconnection. J. Geophys. Res., 112, C11007, doi:10.1029/2006JC003798.

    • Search Google Scholar
    • Export Citation

  • Battisti, D. S., 1988: Dynamics and thermodynamics of a warming event in a coupled tropical atmosphere–ocean model. J. Atmos. Sci., 45, 2889–2919.

    • Search Google Scholar
    • Export Citation

  • Battisti, D. S., and A. C. Hirst, 1989: Interannual variability in a tropical atmosphere–ocean model: Influence of the basic state, ocean geometry and nonlinearity. J. Atmos. Sci., 46, 1687–1712.

    • Search Google Scholar
    • Export Citation

  • Boyd, J. P., 1978: The effects of latitudinal shear on equatorial waves. Part II: Application to the atmosphere. J. Atmos. Sci., 35, 2295–2267.

    • Search Google Scholar
    • Export Citation

  • Cane, M. A., and S. E. Zebiak, 1985: A theory for El Niño and the Southern Oscillation. Science, 228, 1084–1087.

  • Cane, M. A., S. E. Zebiak, and S. C. Dolan, 1986: Experimental forecasts of El Niño. Nature, 321, 827–832.

  • Chu, P. S., 1988: Extratropical forcing and the burst of equatorial westerlies in the western Pacific: A synoptic study. J. Meteor. Soc. Japan, 66, 549–563.

    • Search Google Scholar
    • Export Citation

  • Compo, G. P., G. N. Kiladis, and P. J. Webster, 1999: The horizontal and vertical structure of East Asian winter monsoon pressure surges. Quart. J. Roy. Meteor. Soc., 125, 29–54.

    • Search Google Scholar
    • Export Citation

  • Gill, A. E., 1980: Some simple solutions for heat-induced tropical circulation. Quart. J. Roy. Meteor. Soc., 106, 447–462.

  • Gutzler, D. S., 1991: Interannual fluctuations of intraseasonal variance of near-equatorial zonal winds. J. Geophys. Res., 96 (S01), 3172–3185.

    • Search Google Scholar
    • Export Citation

  • Harrison, D. E., and G. A. Vecchi, 1997: Westerly wind events in the tropical Pacific, 1986–95. J. Climate, 10, 3131–3156.

  • Hendon, H. H., and H. B. Liebmann, 1990: A composite study of onset of the Australian summer monsoon. J. Atmos. Sci., 47, 2227–2240.

  • Hendon, H. H., and H. B. Liebmann, 1994: Organization of convection within the Madden-Julian oscillation. J. Geophys. Res., 99 (D4), 8073–8083.

    • Search Google Scholar
    • Export Citation

  • Hendon, H. H., H. B. Liebmann, and J. D. Glick, 1998: Oceanic Kelvin waves and the Madden–Julian oscillation. J. Atmos. Sci., 55, 88–101.

    • Search Google Scholar
    • Export Citation

  • Huang, R., X. Zang, R. Zhang, and J. Chen, 1998: The westerly anomalies over the tropical Pacific and their dynamical effect on the ENSO cycles during 1980-1994. Adv. Atmos. Sci., 15, 135–151.

    • Search Google Scholar
    • Export Citation

  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc., 77, 437–471.

  • Kao, H.-Y., and J.-Y. Yu, 2009: Contrasting eastern-Pacific and central-Pacific types ENSO. J. Climate, 22, 615–632.

  • Keen, R. A., 1982: The role of cross-equatorial tropical cyclone pairs in the Southern Oscillation. Mon. Wea. Rev., 110, 1405–1416.

  • Keen, R. A., 1988: Equatorial westerly and the Southern Oscillation. Proc. Western Pacific Air-Sea Interaction Workshop, Honolulu, HI, U.S. TOGA, 121–140.

  • Kiladis, G. N., and H. V. Loon, 1988: The Southern Oscillation. Part VII: Meteorological anomalies over the Indian and Pacific sectors associated with the extremes of the oscillation. Mon. Wea. Rev., 116, 120–136.

    • Search Google Scholar
    • Export Citation

  • Kiladis, G. N., G. A. Meehl, and K. M. Weickmann, 1994: Large-scale circulation associated with westerly wind bursts and deep convection over the western equatorial Pacific. J. Geophys. Res., 99 (D9), 18 527–18 544.

    • Search Google Scholar
    • Export Citation

  • Kug, J.-S., F.-F. Jin, and S.-I. An, 2009: Two types of El Niño events: Cold tongue El Niño and warm pool El Niño. J. Climate, 22, 1499–1515.

    • Search Google Scholar
    • Export Citation

  • Larkin, N. K., and D. E. Harrison, 2005a: On the definition of El Niño and associated seasonal average U.S. weather anomalies. Geophys. Res. Lett., 32, L13705, doi:10.1029/2005GL022738.

    • Search Google Scholar
    • Export Citation

  • Larkin, N. K., and D. E. Harrison, 2005b: Global seasonal temperature and precipitation anomalies during El Niño autumn and winter. Geophys. Res. Lett., 32, L16705, doi:10.1029/2005GL022860.

    • Search Google Scholar
    • Export Citation

  • Lau, K. M., and H. Lim, 1982: Thermally driven motions in an equatorial -plane: Hadley and Walker circulations during the winter monsoon. Mon. Wea. Rev., 110, 336–353.

    • Search Google Scholar
    • Export Citation

  • Lau, K. M., M. L. Peng, C. H. Sui, and T. Nakazawa, 1989: Super cloud clusters, westerly wind burst, 30–60 day oscillation, and ENSO: A unified view. J. Meteor. Soc. Japan, 67, 205–219.

    • Search Google Scholar
    • Export Citation

  • Li, C., 1990: Interaction between anomalous winter monsoon in East Asia and El Niño events. Adv. Atmos. Sci., 7, 36–46.

  • Lim, H., and C. P. Chang, 1981: A theory for midlatitude forcing of tropical motions during winter monsoons. J. Atmos. Sci., 38, 2377–2392.

    • Search Google Scholar
    • Export Citation

  • Love, G., 1985a: Cross-equatorial influence of winter hemisphere subtropical cold surges. Mon. Wea. Rev., 113, 1487–1498.

  • Love, G., 1985b: Cross-equatorial interactions during tropical cyclongenesis. Mon. Wea. Rev., 113, 1499–1509.

  • Matsuno, T., 1966: Quasi-geostrophic motions in the equatorial area. J. Meteor. Soc. Japan, 44, 25–43.

  • Rasmusson, E. M., and T. H. Carpenter, 1982: Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation and El Niño. Mon. Wea. Rev., 110, 354–384.

    • Search Google Scholar
    • Export Citation

  • Rong, X., R. Zhang, T. Li, and J. Su, 2011: Upscale feedback of high-frequency winds to ENSO. Quart. J. Roy. Meteor. Soc., 137, 894–907.

    • Search Google Scholar
    • Export Citation

  • Sakai, K., and R. Kawamura, 2009: Remote response of the East Asian winter monsoon to tropical forcing related to El Niño–Southern Oscillation. J. Geophys. Res., 114, D06105, doi:10.1029/2008JD010824.

    • Search Google Scholar
    • Export Citation

  • Smith, T. M., R. W. Reynolds, T. C. Peterson, and J. Lawrimore, 2008: Improvements to NOAA’s historical merged land–ocean surface temperature analysis (1880–2006). J. Climate, 21, 2283–2296.

    • Search Google Scholar
    • Export Citation

  • Sui, C. H., and K. M. Lau, 1992: Multi-scale phenomena in the tropical atmosphere over the western Pacific. Mon. Wea. Rev., 120, 407–430.

    • Search Google Scholar
    • Export Citation

  • Verbickas, S., 1998: Westerly wind bursts in the tropical Pacific. Weather, 53, 282–284.

  • Wang, L., R. Huang, L. Gu, W. Chen, and L. Kang, 2009: Interdecadal variations of the East Asian winter monsoon and their association with quasi-stationary planetary wave activity. J. Climate, 22, 4860–4872.

    • Search Google Scholar
    • Export Citation

  • Webster, P. J., 1987: The elementary monsoon. Monsoons, J. S. Fein and P. L. Stephens, Eds., Wiley Interscience, 3–32.

  • Xu, J., and J. C. L. Chan, 2001: The role of the Asian–Australian monsoon system in the onset time of El Niño events. J. Climate, 14, 418–433.

    • Search Google Scholar
    • Export Citation

  • Xue, Y., T. Smith, and R. W. Reynolds, 2003: Interdecadal changes of 30-yr SST normals during 1871–2000. J. Climate, 16, 1601–1612.

  • Yu, L., and M. M. Rienecher, 1998: Evidence of an extropical atmospheric influence during the onset of the 1997-98 El Niño. Geophys. Res. Lett., 25, 3537–3540.

    • Search Google Scholar
    • Export Citation

  • Zhang, R., and R. Huang, 1998: The dynamic impacts of tropical zonal wind stress in the onset and decay of El Niño events. Part I: Data diagnostics and theoretic analysis. Chin.J. Atmos. Sci., 22, 587–599.

    • Search Google Scholar
    • Export Citation

  • Zhang, R., A. Sumi, and M. Kimoto, 1996: Impact of El Niño on the East Asian monsoon: A diagnostic study of the ’86/87 and ’91/92 events. J. Meteor. Soc. Japan, 74, 49–62.

    • Search Google Scholar
    • Export Citation

  • Zhang, R., G. Zhao, and Y. Tan, 2001: Meridional wind stress anomalies over tropical Pacific and the onset of El Niño. Part I: Data analysis. Adv. Atmos. Sci., 18, 467–480.

    • Search Google Scholar
    • Export Citation
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