Abstract
Vertical distributions of various components of the tropospheric global rotational kinetic energy, enstrophy and available potential energy during July 1979, and the contributions to these from different zonal wave categories were studied. Representative levels in the lower and upper troposphere for the stationary and transient energetics were identified on the basis of different components of energy and enstrophy. The eddy energy and enstrophy contained in different zonal scale components in the lower and upper troposphere were studied to find out the preferred scales for stationary and transient monsoonal motion in the two atmospheric layers. The role of different zonal wave categories in the nonlinear exchanges of energy and enstrophy arising due to stationary-stationary, transient-transient, stationary-transient and observed flow interactions was examined. Stationary and transient global spectra of the aforesaid dynamical variables in terms of the zonal wavenumber(m) with triangular truncation atm = 42 were utilized for this purpose.
It was found from the global average kinetic energy in lower and upper troposphere that the global stationary and transient motions were comparable in the lower troposphere while in the upper troposphere stationary motion dominated over the transient motion. The computed zonal and eddy energy confirmed that the stationary motion was predominantly zonal while the transient motion was dominated by eddies. From the time mean nonlinear interaction of kinetic energy (enstrophy) of observed flow it was seen that the long and short waves as well as the zonal flow gained kinetic energy (enstrophy) from medium waves due to nonlinear interactions. The transfer of available potential energy due to nonlinear interaction was down the scale except for short waves in the upper troposphere. The stationary-transient interaction was found to be an important element of the spatial-temporal varying atmospheric flow.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Asnani G C and Mishra S K 1975 Diabatic heating model of the Indian monsoon;Mon. Weather Rev. 103 115–130
Awade S T, Totagi M Y and Bawiskar S M 1982 Wave to wave interaction and wave to zonal mean flow kinetic energy exchange during contrasting monsoon years;Pure Appl. Geophys. 115 1187–1208
Baer F 1972 An alternate scale representation of atmospheric energy spectra;J. Atmos. Sci. 29 649–664
Baer F 1974 Hemispheric spectral statistics of available potential energy;J. Atmos. Sci. 31 932–941
Boer G J and Shepherd T G 1983 Large-scale two-dimensional turbulence in the atmosphere;J. Atmos. Sci. 40 164–183
Burrows W R 1976 A diagnostic study of atmospheric spectral kinetic energetic;J. Atmos. Sci. 33 2308–2321
Chakraborty D R and Mishra S K 1993 Nonlinear kinetic energy transfer in the upper troposphere during summer monsoon, 1979;J. Geophys. Res.-Atmos. 98 D12 23223–23233
Chen T C and Wiin-Nielsen A 1978 On nonlinear cascades of atmospheric energy and enstrophy in a two-dimensional spectral index;Tellus 30 312–322
Desai S S and Mishra S K 1993 Global spectra of energy and enstrophy and their fluxes during July 1979;Proc. Indian Acad. Sci. (Earth Planet. Sci.) 102 2329–350
Desai S S 1992 Spectral representation of various meteorological parameters during monsoon; M.Sc. Thesis University of Poona
Fjortoft R 1953 On the changes in the spectral distribution of kinetic energy for two-dimensional nondivergent flow;Tellus 5 225–230
Kanamitsu M, Krishnamurti T N and Depredine E 1972 On scale interaction in the tropics during northern summer;J. Atmos. Sci. 29 698–706
Krishnamurti T N, Daggupati S N, Fein J, Kanamitsu M and Lee J D 1973 Tibetan high and upper tropospheric tropical circulation during northern summer;Bull. Am. Meteorol. Soc. 54 1234–1244
Kubota S 1959 Surface spherical harmonic representations of the system of equations for analysis;Pap. Met. Geophys. 10 145–166
Lambert S J 1981 A diagnostic study of global energy and enstrophy fluxes and spectra;Tellus 33 411–414
Lambert S J 1984 A global available potential energy-kinetic energy budget in terms of the twodimensional wavenumber for the FGGE year;Atmosphere-Ocean 22 265–282
Murakami T 1981 Summer mean energetics for standing and transient eddies in the wavenumber domain;Monsoon Dynamics (ed.) S J Lighthill and R P Pearce (Cambridge Univ. Press) pp. 65–80
Saltzman B 1957 Equations governing the energetics of the larger scales of atmospheric turbulence in the domain of wavenumber;J. Meteorol. 14 513–523
Saltzman B 1970 Large-scale atmospheric energetics in the wavenumber domain;Rev. Geophys. Space Phys. 8 289–302
Shepherd T G 1987 A spectral view of nonlinear fluxes and stationary-transient interaction in the atmosphere;J. Atmos. Sci. 44 1166–1178
Smagorinsky J, Manabe S and Holloway J L Jr. 1965 Numerical results from a nine level general circulation model of the atmosphere;Mon. Weather Rev. 93 727–768
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Desai, S.S., Mishra, S.K. Spectral analysis of monsoonal global energy and enstrophy and their nonlinear exchanges in the zonal wavenumber domain. Proc. Indian Acad. Sci. (Earth Planet Sci.) 103, 469–488 (1994). https://doi.org/10.1007/BF02839291
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02839291