The Theoretician’s Clouds—Heavier or Lighter than Air? On Densities in Atmospheric Thermodynamics

Joachim Pelkowski JRG Dynamical Systems, KlimaCampus, Universität Hamburg, Grindelberg, Germany

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Thomas Frisius JRG Dynamical Systems, KlimaCampus, Universität Hamburg, Grindelberg, Germany

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Abstract

Threefold densities may be introduced into atmospheric thermodynamics. For rainless clouds the general indirect or implicit conclusion is that they are denser than moist air under the same circumstances, although in a classic treatise a different conclusion was reached, to the effect that cloudy air (containing water and/or ice) is less dense than moist air under the same pressure and temperature. By reconsidering carefully different ways of determining densities, any doubts that may linger after reading the scant literature dealing explicitly with the density of a cloud are dispelled.

Corresponding author address: Joachim Pelkowski, KlimaCampus, Grindelberg 5, D-20144, Germany. E-mail: joachim.pelkowski@zmaw.de

Abstract

Threefold densities may be introduced into atmospheric thermodynamics. For rainless clouds the general indirect or implicit conclusion is that they are denser than moist air under the same circumstances, although in a classic treatise a different conclusion was reached, to the effect that cloudy air (containing water and/or ice) is less dense than moist air under the same pressure and temperature. By reconsidering carefully different ways of determining densities, any doubts that may linger after reading the scant literature dealing explicitly with the density of a cloud are dispelled.

Corresponding author address: Joachim Pelkowski, KlimaCampus, Grindelberg 5, D-20144, Germany. E-mail: joachim.pelkowski@zmaw.de
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  • Bohren, C. F., and B. A. Albrecht, 1998: Atmospheric Thermodynamics. Oxford University Press, 402 pp.

  • Bowen, R. M., 1980: Incompressible porous media models by use of the theory of mixtures. Int. J. Eng. Sci., 18, 11291148.

  • Chalon, J.-P., 2002: Combien Pèse un Nuage? EDP Sciences, 187 pp.

  • Drew, D. A., and S. L. Passman, 1999: Theory of Multicomponent Fluids. Springer, 308 pp.

  • Dufour, L., and J. van Mieghem, 1975: Thermodynamique de l’Atmosphère. Institut Royal Météorologique de Belgique, 278 pp.

  • Emanuel, K. A., 1994: Atmospheric Convection. Oxford University Press, 592 pp.

  • Frisius, T., and U. Wacker, 2007: Das massenkonsistente axialsymmetrische Wolkenmodell HURMOD. Deutsche Wetterdienst Research Rep. 85, 42 pp.

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  • Glickman, T. S., Ed., 2000: Glossary of Meteorology. 2nd ed. Amer. Meteor. Soc., 850 pp.

  • Goodman, M. A., and S. C. Cowin, 1972: A continuum theory for granular materials. Arch. Ration. Mech. Anal., 44, 249266.

  • Hutter, K., and K. Jöhnk, 2004: Continuum Methods of Physical Modeling. Springer, 635 pp.

  • Iribarne, J. V., and W. L. Godson, 1981: Atmospheric Thermodynamics. 2nd ed. Reidel, 259 pp.

  • Salby, M., 1996: Fundamentals of Atmospheric Physics. Academic Press, 627 pp.

  • Wallace, J. M., and P. V. Hobbs, 2006: Atmospheric Science: An Introductory Survey. 2nd ed. Academic Press, 483 pp.

  • Wegener, A., 1911: Thermodynamik der Atmosphäre. Leipzig Verlag von J. A. Barth, 331 pp.

  • Zdunkowski, W., and A. Bott, 2004: Thermodynamics of the Atmosphere. Cambridge University Press, 251 pp.

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