Global Angular Momentum Fluxes in Height Coordinates

Joseph Egger Meteorologisches Institut, Universität München, Munich, Germany

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Klaus-Peter Hoinka Institut für Physik der Atmosphäre, DLR, Oberpfaffenhofen, Germany

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Abstract

While time and zonal mean budgets of axial angular momentum (AAM) have been presented in pressure coordinates and also in isentropic coordinates, AAM budgets in height coordinates have not been published yet. The results of such an analysis on the basis of the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) winter data are presented in this paper, which includes explicitly evaluated vertical eddy fluxes of momentum and mass as new features. As expected, AAM fluxes related to the Hadley cell are dominant. Transient vertical AAM fluxes are directed upward at the midlatitudes. Transient mass transports are not negligible, while triple terms are unimportant. Problems with the global balance of torques acting at the surface are discussed as well as those of mass conservation.

Corresponding author address: Joseph Egger, Meteorological Institute, University of Munich, Theresienstr. 37, Munich 80333, Germany. E-mail: j.egger@lrz.uni-muenchen.de

Abstract

While time and zonal mean budgets of axial angular momentum (AAM) have been presented in pressure coordinates and also in isentropic coordinates, AAM budgets in height coordinates have not been published yet. The results of such an analysis on the basis of the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) winter data are presented in this paper, which includes explicitly evaluated vertical eddy fluxes of momentum and mass as new features. As expected, AAM fluxes related to the Hadley cell are dominant. Transient vertical AAM fluxes are directed upward at the midlatitudes. Transient mass transports are not negligible, while triple terms are unimportant. Problems with the global balance of torques acting at the surface are discussed as well as those of mass conservation.

Corresponding author address: Joseph Egger, Meteorological Institute, University of Munich, Theresienstr. 37, Munich 80333, Germany. E-mail: j.egger@lrz.uni-muenchen.de
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  • Egger, J., 2006: The moisture torque. Meteor. Z., 15, 671673.

  • Egger, J., and K.-P. Hoinka, 2010: Regional contributions to isentropic pressure torques. Mon. Wea. Rev., 138, 41754185.

  • Gallimore, R., and D. Johnson, 1981: The forcing of the meridional circulation of the isentropic zonally averaged circumpolar vortex. J. Atmos. Sci., 38, 583599.

    • Search Google Scholar
    • Export Citation
  • Hantel, M., and J. Hacker, 1978: On the vertical eddy transports in the Northern Atmosphere. 2. Vertical eddy momentum transport for summer and winter. J. Geophys. Res., 83, 13051318.

    • Search Google Scholar
    • Export Citation
  • Held, I., and T. Schneider, 1999: The surface branch of the zonally averaged mass transport circulation in the troposphere. J. Atmos. Sci., 56, 16881697.

    • Search Google Scholar
    • Export Citation
  • Holton, J., 1992: An Introduction to Dynamic Meteorology. Academic Press, 511 pp.

  • Johnson, D., 1980a: A generalized transport equation for use with meteorological coordinate systems. Mon. Wea. Rev., 108, 733745.

  • Johnson, D., 1980b: The forcing and maintenance of global monsoonal circulations: An isentropic analysis. Advances in Geophysics, Vol. 31, Academic Press, 43–329.

    • Search Google Scholar
    • Export Citation
  • Oort, A., and J. Peixoto, 1983: Global angular momentum and energy balance requirements from observations. Advances in Geophysics, Vol. 25, Academic Press, 355–490.

    • Search Google Scholar
    • Export Citation
  • Peixoto, J., and A. Oort, 1992: Physics of Climate. American Institute of Physics, 320 pp.

  • Rosenlof, K., D. Stevens, J. Anderson, and P. Cieselski, 1986: The Walker Circulation with observed zonal winds, a mean Hadley cell, and cumulus friction. J. Atmos. Sci., 43, 449467.

    • Search Google Scholar
    • Export Citation
  • Starr, V., and R. White, 1951: A hemispherical study of the atmospheric angular-momentum balance. Quart. J. Roy. Meteor. Soc., 77, 215225.

    • Search Google Scholar
    • Export Citation
  • Trenberth, K., 1987: The role of eddies in maintaining the westerlies in the Southern Hemisphere winter. J. Atmos. Sci., 44, 14981508.

    • Search Google Scholar
    • Export Citation
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