Editorial Type:
Article
Article Type:
Research Article

The Mechanical Impact of the Tibetan Plateau on the Seasonal Evolution of the South Asian Monsoon

Hyo-Seok Park California Institute of Technology, Pasadena, California

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John C. H. Chiang Department of Geography, and Berkeley Atmospheric Science Center, University of California, Berkeley, Berkeley, California

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Simona Bordoni California Institute of Technology, Pasadena, California

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Print Publication:
01 Apr 2012
DOI:
https://doi.org/10.1175/JCLI-D-11-00281.1
Page(s):
2394–2407
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Abstract

The impact of the Tibetan Plateau on the South Asian monsoon is examined using a hierarchy of atmospheric general circulation models. During the premonsoon season and monsoon onset (April–June), when westerly winds over the Southern Tibetan Plateau are still strong, the Tibetan Plateau triggers early monsoon rainfall downstream, particularly over the Bay of Bengal and South China. The downstream moist convection is accompanied by strong monsoonal low-level winds. In experiments where the Tibetan Plateau is removed, monsoon onset occurs about a month later, but the monsoon circulation becomes progressively stronger and reaches comparable strength during the mature phase. During the mature and decaying phase of monsoon (July–September), when westerly winds over the Southern Tibetan Plateau almost disappear, monsoon circulation strength is not much affected by the presence of the Tibetan Plateau.

A dry dynamical core with east–west-oriented narrow mountains in the subtropics consistently simulates downstream convergence with background zonal westerlies over the mountain. In a moist atmosphere, the mechanically driven downstream convergence is expected to be associated with significant moisture convergence. The authors speculate that the mechanically driven downstream convergence in the presence of the Tibetan Plateau is responsible for zonally asymmetric monsoon onset, particularly over the Bay of Bengal and South China.

Corresponding author address: Hyo-Seok Park, MC 100-23, California Institute of Technology, Pasadena, CA 91125-2300. E-mail: hyo@caltech.edu

Abstract

The impact of the Tibetan Plateau on the South Asian monsoon is examined using a hierarchy of atmospheric general circulation models. During the premonsoon season and monsoon onset (April–June), when westerly winds over the Southern Tibetan Plateau are still strong, the Tibetan Plateau triggers early monsoon rainfall downstream, particularly over the Bay of Bengal and South China. The downstream moist convection is accompanied by strong monsoonal low-level winds. In experiments where the Tibetan Plateau is removed, monsoon onset occurs about a month later, but the monsoon circulation becomes progressively stronger and reaches comparable strength during the mature phase. During the mature and decaying phase of monsoon (July–September), when westerly winds over the Southern Tibetan Plateau almost disappear, monsoon circulation strength is not much affected by the presence of the Tibetan Plateau.

A dry dynamical core with east–west-oriented narrow mountains in the subtropics consistently simulates downstream convergence with background zonal westerlies over the mountain. In a moist atmosphere, the mechanically driven downstream convergence is expected to be associated with significant moisture convergence. The authors speculate that the mechanically driven downstream convergence in the presence of the Tibetan Plateau is responsible for zonally asymmetric monsoon onset, particularly over the Bay of Bengal and South China.

Corresponding author address: Hyo-Seok Park, MC 100-23, California Institute of Technology, Pasadena, CA 91125-2300. E-mail: hyo@caltech.edu
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  • Abe, M., A. Kitoh, and T. Yasunari, 2003: An evolution of the Asian summer monsoon associated with mountain uplift—Simulation with the MRI atmosphere–ocean coupled GCM. J. Meteor. Soc. Japan, 81, 909–933.

    • Search Google Scholar
    • Export Citation

  • Annamalai, H., K. Hamilton, and K. R. Sperber, 2007: South Asian summer monsoon and its relationship with ENSO in the IPCC AR4 simulations. J. Climate, 20, 1071–1092.

    • Search Google Scholar
    • Export Citation

  • Boos, W. R., 2008: Wind–evaporation feedback, angular momentum conservation, and abrupt onset of monsoons. Ph.D dissertation, MIT, 174 pp.

    • Search Google Scholar
    • Export Citation

  • Boos, W. R., and K. A. Emanuel, 2009: Annual intensification of the Somali jet in a quasi-equilibrium framework: Observational composites. Quart. J. Roy. Meteor. Soc., 135, 319–335.

    • Search Google Scholar
    • Export Citation

  • Boos, W. R., and Z. Kuang, 2010: Dominant control of the South Asian monsoon by orographic insulation versus plateau heating. Nature, 463, 218–222.

    • Search Google Scholar
    • Export Citation

  • Bordoni, S., and T. Schneider, 2008: Monsoons as eddy-mediated regime transitions of the tropical overturning circulation. Nat. Geosci., 1, 515–519, doi:10.1038/ngeo248.

    • Search Google Scholar
    • Export Citation

  • Charney, J. G., 1975: Dynamics of deserts and drought in Sahel. Quart. J. Roy. Meteor. Soc., 101, 193–202.

  • Chou, C., J. D. Neelin, and H. Su, 2001: Ocean–atmosphere–land feedbacks in an idealized monsoon. Quart. J. Roy. Meteor. Soc., 127, 1869–1891.

    • Search Google Scholar
    • Export Citation

  • Cook, K. H., and I. M. Held, 1992: The stationary response to large-scale orography in a general circulation model and a linear model. J. Atmos. Sci., 49, 525–539.

    • Search Google Scholar
    • Export Citation

  • Emanuel, K. A., 1987: An air–sea interaction model of intraseasonal oscillations in the tropics. J. Atmos. Sci., 52, 1529–1534.

  • Emanuel, K. A., J. D. Neelin, and C. S. Bretherton, 1994: On large-scale circulations in convecting atmosphere. Quart. J. Roy. Meteor. Soc., 120, 1111–1143.

    • Search Google Scholar
    • Export Citation

  • Flohn, H., 1957: Large-scale aspects of the “summer monsoon” in South and East Asia. J. Meteor. Soc. Japan, 35, 180–186.

  • Frierson, D. M. W., and N. A. Davis, 2011: The seasonal cycle of midlatitude static stability over land and ocean in global reanalyses. Geophys. Res. Lett., 38, L13803, doi:10.1029/2011GL047747.

    • Search Google Scholar
    • Export Citation

  • Gadgil, S., 2003: The Indian monsoon and its variability. Annu. Rev. Earth Planet. Sci., 31, 429–467.

  • GFDL Global Atmospheric Model Development Team, 2004: The new GFDL global atmosphere and land model AM2–LM2: Evaluation with prescribed SST simulations. J. Climate, 17, 4641–4673.

    • 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.

  • Hahn, D. G., and S. Manabe, 1975: The role of mountains in the South Asian monsoon circulation. J. Atmos. Sci., 32, 1515–1541.

  • Held, I. M., and M. J. Suarez, 1994: A proposal for the intercomparison of the dynamical cores of atmospheric general circulation models. Bull. Amer. Meteor. Soc., 73, 1825–1830.

    • Search Google Scholar
    • Export Citation

  • Held, I. M., M.-F. Ting, and H.-I. Wang, 2002: Northern winter stationary waves: Theory and modeling. J. Climate, 15, 2125–2144.

  • Hsu, H. H., C. T. Terng, and C. T. Chen, 1999: Evolution of large-scale circulation and heating during the first transition of Asian summer monsoon. J. Climate, 12, 793–810.

    • Search Google Scholar
    • Export Citation

  • Kang, I.-S., and I. M. Held, 1986: Linear and nonlinear diagnostic models of stationary eddies in the upper troposphere during northern summer. J. Atmos. Sci., 43, 3045–3057.

    • Search Google Scholar
    • Export Citation

  • Kiehl, J. T., J. J. Hack, G. B. Bonan, B. A. Boville, D. L. Williamson, and P. J. Rasch, 1998: The National Center for Atmospheric Research Community Climate Model: CCM3. J. Climate, 11, 1131–1149.

    • Search Google Scholar
    • Export Citation

  • Kutzbach, J. E., P. J. Guetter, W. F. Ruddiman, and W. L. Prell, 1989: The sensitivity of climate to Late Cenozoic uplift in southern Asia and the American west: Numerical experiments. J. Geophys. Res., 103, 14 451–14 510.

    • Search Google Scholar
    • Export Citation

  • Lin, S.-J., 2004: A “vertically Lagrangian” finite-volume dynamical core for global models. Mon. Wea. Rev., 132, 2293–2307.

  • Luo, H., and M. Yanai, 1984: The large-scale circulation and heat source over the Tibetan Plateau and surrounding areas during the early summer of 1979. Part II: Heat and moisture budgets. Mon. Wea. Rev., 112, 966–989.

    • Search Google Scholar
    • Export Citation

  • Molnar, P., W. R. Boos, and D. S. Battisti, 2010: Orographic controls on climate and paleoclimate of Asia: Thermal and mechanical roles for the Tibetan Plateau. Annu. Rev. Earth Planet. Sci., 38, 77–102.

    • Search Google Scholar
    • Export Citation

  • Navarra, A., W. F. Stern, and K. Miyakoda, 1994: Reduction of the Gibbs oscillation in spectral model simulations. J. Climate, 7, 1169–1183.

    • Search Google Scholar
    • Export Citation

  • Neelin, J. D., I. M. Held, and K. H. Cook, 1987: Evaporation–wind feedback and low-frequency variability in the tropical atmosphere. J. Atmos. Sci., 44, 2341–2348.

    • Search Google Scholar
    • Export Citation

  • Prell, W. L., and J. E. Kutzbach, 1992: Sensitivity of the Indian monsoon to forcing parameters and implications for its evolution. Nature, 360, 647–652.

    • Search Google Scholar
    • Export Citation

  • Prive, N. C., and R. A. Plumb, 2007: Monsoon dynamics with interactive forcing. Part II: Impact of eddies and asymmetric geometries. J. Atmos. Sci., 64, 1431–1442.

    • Search Google Scholar
    • Export Citation

  • Rodwell, M. J., and B. J. Hoskins, 2001: Subtropical anticyclones and summer monsoons. J. Climate, 14, 3192–3211.

  • Sato, T., and F. Kimura, 2007: How does the Tibetan Plateau affect the transition of Indian monsoon rainfall? Mon. Wea. Rev., 135, 2006–2015.

    • Search Google Scholar
    • Export Citation

  • Smith, R. B., 1980: Linear theory of stratified hydrostatic flow past an isolated mountain. Tellus, 32A, 348–364.

  • 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, 1403–1420.

    • Search Google Scholar
    • Export Citation

  • Takahashi, K., and D. S. Battisti, 2007b: Processes controlling the mean tropical Pacific precipitation pattern. Part II: The SPCZ and the South Pacific dry zone. J. Climate, 20, 5696–5706.

    • Search Google Scholar
    • Export Citation

  • Uppala, S. M., and Coauthors, 2005: The ERA-40 Re-Analysis. Quart. J. Roy. Meteor. Soc., 131, 2961–3012.

  • Webster, P. J., and Coauthors, 1998: Monsoons—Processes, predictability, and the prospects for prediction. J. Geophys. Res., 103, 14 451–14 510.

    • Search Google Scholar
    • Export Citation

  • Wu, G.-X., and Y.-S. Zhang, 1998: Tibetan Plateau forcing and the timing of the monsoon onset over South Asia and the South China Sea. Mon. Wea. Rev., 126, 913–927.

    • Search Google Scholar
    • Export Citation

  • Wu, G.-X., and Coauthors, 2007: The influence of mechanical and thermal forcing by the Tibetan Plateau on Asian climate. J. Hydrometeor., 8, 770–789.

    • Search Google Scholar
    • Export Citation

  • Xie, P., and P. A. Arkin, 1997: Global precipitation: A 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bull. Amer. Meteor. Soc., 78, 2539–2558.

    • Search Google Scholar
    • Export Citation

  • Yanai, M., and G. X. Wu, 2006: Effects of the Tibetan Plateau. The Asian Monsoon, B. Wang, Ed., Springer, 513–549.

  • Yasunari, T., K. Saito, and K. Takata, 2006: Relative role of large-scale orography and land surface processes in the global hydroclimate. Part I: Impacts on monsoon systems and the tropics. J. Hydrometeor., 7, 626–641.

    • Search Google Scholar
    • Export Citation

  • Yeh, T. C., S. W. Luo, and P. C. Chu, 1957: The wind structure and heat balance in the lower troposphere over Tibetan Plateau and its surrounding. Acta Meteor. Sin., 28, 108–121.

    • Search Google Scholar
    • Export Citation

  • Yin, M. T., 1949: A synoptic–aerologic study of the onset of the summer monsoon over India and Burma. J. Meteor., 6, 394–400.

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