pure and applied geophysics

, Volume 120, Issue 2, pp 229–248 | Cite as

Meridional transport of sensible heat in contrasting monsoon activity: Spherical harmonic analysis

  • S. T. Awade
  • S. M. Bawiskar


Spherical harmonic analysis is made of the grid point values of geopotential heights at 700 mb and 300 mb levels for the months April to August for the years 1967 and 1972. The year 1967 is a good monsoon year and 1972 is a bad monsoon year in India. Meridional transport of sensible heat is obtained in wave number domain using spherical harmonic coefficients at 500 mb level form=1 to 10 andn−m=0 to 10, wherem represents the wave number round the globe andn−m gives the numbers of zero points from north pole to south pole excluding the poles themselves.

Large northward transports of sensible heat in the month of May and in the monsoon months at the subtropics are characteristic of bad monsoon. Wave 1 transports sensible heat southward (forn−m=0) and wave 2 transports sensible heat northward (forn−m=4). Strengthening of wave 1 is conducive to good monsoon year and strengthening of wave 2 is conducive to bad monsoon year. These are the same features obtained in Fourier analysis. The contrasting features exist in waves 1 and 2 both in good and in bad monsoon and are better defined in the present analysis than in the Fourier analysis of the earlier study. However, waves 1 and 2 reveal clearer contrast in the present analysis than in the Fourier analysis. Bad monsoon activity is associated with large divergence of heart at subtropics and large convergence of heat at extra tropics.

Key words

Meridional transport Monsoon Sensible heat 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Asnani, G. C., andAwade, S. T. (1978),Monitoring of Semi-permanent Troughs and Ridges in Relation to Monsoon, Indian J. Met. Hydrol. Geophys.29, 163–169.Google Scholar
  2. Awade, S. T., Asnani, G. C., andKeshavamurty, R. N. (1975),Spherical Harmonic Analysis of the Normal Constant Pressure Charts in the Northern Hemisphere, Arch. Met. Geophys. Biokl. Ser A24, 189–205.Google Scholar
  3. Awade, S. T., Raja Rao, K. S., andAsnani, G. C. (1978),The Meridional Transport of Momentum in the Wave Number Regime during the Contrasting Monsoon Years, Indian J. Met. Hydrol. Geophys.29, 283–292.Google Scholar
  4. Awade, S. T. (1979),Some Features of the Large-scale Circulation during Indian Southwest Monsoon, Ph. D. thesis, University of Poona, Poona-411007, India, 227 pp.Google Scholar
  5. Awade, S. T., Totagi, M. Y., andSikka, D. R. (1981),Proceedings of International Conference on Early Results of FGGE and Large-scale Aspects of Its Monsoon Experiments, Tallahassee, Florida, U.S.A., 12–17 January 1981, pp. 5–52 to 5–56.Google Scholar
  6. Eliasen, E., andMachenhauer, B. (1965),A Study of the Fluctuations of the Atmospheric Planetary Flow Patterns Represented by Spherical Harmonics, Tellus17, 220–228.Google Scholar
  7. Eliasen, E., andMachenhauer, B. (1969),On the Observed Large-scale Atmospheric Wave-motion, Tellus21, 149–166.Google Scholar
  8. Harihara, P. S., Nagasubramanian, M. R., andChangraney, T. G. (1973),Rainfall and Floods/Droughts in India during the 1972 Southwest Monsoon Period, Indian J. Met. Geophys.,24, 215–222.Google Scholar
  9. Kanamitsu, M., andKrishnamurti, T. N. (1978),Northern Summer tropical Circulations during Drought and Normal Rainfall Months, Mon. Weath. Rev.106, 331–347.Google Scholar
  10. Kanamitsu, M. Analysis of Monsoonal Quasi-stationary Systems as Revealed in a Real-data Prediction Experiment, Monsoon Dynamics (Cambridge University Press, Cambridge 1981), pp. 147–164.Google Scholar
  11. Keshavamurty, R. N., andAwade, S. T. (1974),Dynamical Abnormalities Associated with Drough in the Asiatic Summer Monsoon, Indian J. Met. Geophys.25, 257–264.Google Scholar
  12. Krishnamurti, T. N., Astling, E., andKanamitsu, M. (1975),200 mb Wind June, July and August, 1972, Department of Meteorology, Tallahassee Florida State University, 111pp.Google Scholar
  13. Lorenz, E. N. (1966),Computations of Balance of Angular Momentum and Poleward Transport of Heat, Observational Studies of the Atmospheric General Circulation, Scientific Report, No. 2, Planetary Circulation Project, Dept. of Met., Massachusetts Institute of Technology, Cambridge, Massachusetts, pp. 32–65.Google Scholar
  14. Murakami, T. (1975),Internanual Cloudiness Changes, Mon. Weath. Rev.,103, 996–1006.Google Scholar
  15. Oort, A. H., andRasmusson, E. M. (1971),Atmospheric Circulation Statistics, NOAA, Professional Paper 5, U.S. Department of Commerce, 325 pp.Google Scholar
  16. Saltzman, B. (1965),On the Theory of the Winter Average Perturbations in the Troposphere and Stratosphere, Mon. Weath. Rev.93, 195–211.Google Scholar
  17. Unni Nayar, M. S., andMurakami, T. (1978),Temporal Variations in the Northern Hemispheric Summer Circulations, Indian J. Met. Hydrol. Geophys.29, 170–186.Google Scholar
  18. World Meteorological Organisation (1973),Significant Weather in 1972, WMO Bull.12, 99–107, Geneva, Switzerland.Google Scholar

Copyright information

© Birkhäuser Verlag 1982

Authors and Affiliations

  • S. T. Awade
  • S. M. Bawiskar
    • 1
  1. 1.Indian Institute of Tropical MeteorologyPuneIndia

Personalised recommendations