Abstract
Monsoons are generally viewed as planetary-scale sea-breeze circulations, caused by contrasts in the thermal properties between oceans and land surfaces that lead to thermal contrasts upon radiative heating1,2. But the radiative heating evolves gradually with the seasons, whereas the onset of monsoon precipitation, and the associated circulation changes such as reversal of surface winds, occur rapidly3,4. Here we use reanalysis data to show that the onset of the Asian monsoon marks a transition between two circulation regimes that are distinct in the degree to which eddy momentum fluxes control the strength of the tropical overturning circulation. Rapid transitions of the circulation between the two regimes can occur as a result of feedbacks between large-scale extratropical eddies and the tropical circulation5. Using simulations with an aquaplanet general circulation model, we demonstrate that rapid, eddy-mediated monsoon transitions occur even in the absence of surface inhomogeneities, provided the planet surface has sufficiently low thermal inertia. On the basis of these results, we propose a view of monsoons in which feedbacks between large-scale extratropical eddies and the tropical circulation are essential for the development of monsoons, whereas surface inhomogeneities such as land-sea contrasts are not.
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References
Webster, P. J. in Monsoons (eds Fein, J. S. & Stephens, P. L.) 3–32 (Wiley, New York, 1987).
Webster, P. J. & Fasullo, J. Encyclopedia of Atmospheric Sciences 1370–1385 (Academic, New York, 2003).
Yin, M. T. A synoptic-aerologic study of the onset of the summer monsoon over India and Burma. J. Meteorol. 6, 393–400 (1949).
Lau, K.-M. & Yang, S. Seasonal variation, abrupt transition, and intraseasonal variability associated with the Asian summer monsoon in the GLA GCM. J. Clim. 9, 965–985 (1996).
Schneider, T. & Bordoni, S. Eddy-mediated regime transitions in the seasonal cycle of a Hadley circulation and implications for monsoon dynamics. J. Atmos. Sci. 65, 915–934 (2008).
Plumb, R. A. & Hou, A. Y. The response of a zonally symmetric atmosphere to subtropical thermal forcing: Threshold behavior. J. Atmos. Sci. 49, 1790–1799 (1992).
Emanuel, K. A. On thermally direct circulations in moist atmospheres. J. Atmos. Sci. 52, 1529–1534 (1995).
Plumb, R. A. in The Global Circulation of the Atmosphere (eds Schneider, T. & Sobel, A. H.) 252–266 (Princeton UP, Princeton and Oxford, 2007).
Privé, N. C. & Plumb, R. A. Monsoon dynamics with interactive forcing. Part I: Axisymmetric studies. J. Atmos. Sci. 64, 1417–1430 (2007).
Gadgil, S. The Indian monsoon and its variability. Annu. Rev. Earth Planet. Sci. 31, 429–467 (2003).
Li, C. & Yanai, M. The onset and interannual variability of the Asian summer monsoon in relation to land-sea thermal contrast. J. Clim. 9, 358–375 (1996).
Held, I. M. & Hou, A. Y. Nonlinear axially symmetric circulations in a nearly inviscid atmosphere. J. Atmos. Sci. 37, 515–533 (1980).
Lindzen, S. R. & Hou, A. Y. Hadley circulations for zonally averaged heating centered off the equator. J. Atmos. Sci. 45, 2416–2427 (1988).
Schneider, T. The general circulation of the atmosphere. Annu. Rev. Earth Planet. Sci. 34, 655–688 (2006).
Walker, C. C. & Schneider, T. Eddy influences on Hadley circulations: Simulations with an idealized GCM. J. Atmos. Sci. 63, 3333–3350 (2006).
Webster, P. J. & Holton, J. R. Cross-equatorial response to middle-latitude forcing in a zonally varying basic state. J. Atmos. Sci. 39, 722–733 (1982).
O’Gorman, P. A. & Schneider, T. The hydrological cycle over a wide range of climates simulated with an idealized GCM. J. Clim. 21, 3815–3832 (2008).
Trenberth, K. E. & Caron, J. M. Estimates of meridional atmosphere and ocean heat transports. J. Clim. 14, 3433–3443 (2001).
Bordoni, S. On the Role of Eddies in Monsoonal Circulations: Observations and Theory. PhD thesis, Univ. California, Los Angeles (2007).
Fennessy, M. J. et al. The simulated Indian monsoon: A GCM sensitivity study. J. Clim. 7, 33–43 (1994).
Chou, C., Neelin, J. D. & Su, H. Ocean-atmosphere-land feedbacks in an idealized monsoon. Q. J. R. Meteorol. Soc. 127, 1869–1891 (2001).
Privé, N. C. & Plumb, R. A. Monsoon dynamics with interactive forcing. Part II: Impact of eddies and asymmetric geometries. J. Atmos. Sci. 64, 1431–1442 (2007).
Chao, W. C. & Chen, B. The origin of monsoons. J. Atmos. Sci. 58, 3497–3507 (2001).
Neelin, J. D., Held, I. M. & Cook, K. H. Evaporation-wind feedback and low-frequency variability in the tropical atmosphere. J. Atmos. Sci. 44, 2341–2348 (1987).
Emanuel, K. A. An air–sea interaction model of intraseasonal oscillations in the tropics. J. Atmos. Sci. 44, 2324–2340 (1987).
Numaguti, A. Dynamics and energy balance of the Hadley circulation and the tropical precipitation zones. Part II: Sensitivity to meridional SST distribution. J. Atmos. Sci. 52, 1128–1141 (1995).
Yano, J.-I. & McBride, J. L. An aquaplanet monsoon. J. Atmos. Sci. 55, 1373–1399 (1998).
Xie, S.-P. & Saiki, N. Abrupt onset and slow seasonal evolution of summer monsoon in an idealized GCM simulation. J. Meteorol. Soc. Japan 77, 949–968 (1999).
Huffman, G. J. et al. Global precipitation at one-degree daily resolution from multisatellite observations. J. Hydrometeorol. 2, 36–50 (2001).
Uppala, S. M. et al. The ERA-40 reanalysis. Q. J. R. Meteorol. Soc. 131, 2961–3012 (2005).
Acknowledgements
This work was supported by the Davidow Discovery Fund, a David and Lucile Packard Fellowship, a Moore Postdoctoral Fellowship and the National Science Foundation (grant no. ATM-0450059). The simulations were carried out on Caltech’s Geological and Planetary Science Dell Cluster, and the reanalysis data were provided by the National Center for Atmospheric Research (which is sponsored by the National Science Foundation). Part of the research was carried while S.B. was with the Department of Atmospheric and Oceanic Sciences at UCLA (supported by a UCLA Dissertation Year Fellowship). We thank B. Stevens for comments on drafts of this paper.
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Bordoni, S., Schneider, T. Monsoons as eddy-mediated regime transitions of the tropical overturning circulation. Nature Geosci 1, 515–519 (2008). https://doi.org/10.1038/ngeo248
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DOI: https://doi.org/10.1038/ngeo248
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