Editorial Type:
Article
Article Type:
Research Article

Possible Effects of Collisional Breakup on Mixed-Phase Deep Convection Simulated by a Spectral (Bin) Cloud Model

Axel Seifert Institut für Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe/Universität Karlsruhe, Karlsruhe, Germany

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Alexander Khain Institute of the Earth Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel

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Ulrich Blahak Institut für Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe/Universität Karlsruhe, Karlsruhe, Germany

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Klaus D. Beheng Institut für Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe/Universität Karlsruhe, Karlsruhe, Germany

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Print Publication:
01 Jun 2005
DOI:
https://doi.org/10.1175/JAS3432.1
Page(s):
1917–1931
Restricted access

Abstract

The effects of the collisional breakup of raindrops are investigated using the Hebrew University Cloud Model (HUCM). The parameterizations, which are combined in the new breakup scheme, are those of Low and List, Beard and Ochs, as well as Brown. A sensitivity study reveals strong effects of collisional breakup on the precipitation formation in mixed-phase deep convective clouds for strong as well as for weak precipitation events. Collisional breakup reduces the number of large raindrops, increases the number of small raindrops, and, as a consequence, decreases surface rain rates and considerably reduces the speed of rain formation. In addition, it was found that including breakup can lead to a more intense triggering of secondary convective cells. But a statistical comparison with observed raindrop size distributions shows that the parameterizations might systematically overestimate collisional breakup.

Corresponding author address: Dr. Axel Seifert, Deutscher Wetterdienst, GB Forschung und Entwicklung, Kaisorleistr. 42, Offenbach a. M., Germany. Email: axel.seifert@dwd.de

Abstract

The effects of the collisional breakup of raindrops are investigated using the Hebrew University Cloud Model (HUCM). The parameterizations, which are combined in the new breakup scheme, are those of Low and List, Beard and Ochs, as well as Brown. A sensitivity study reveals strong effects of collisional breakup on the precipitation formation in mixed-phase deep convective clouds for strong as well as for weak precipitation events. Collisional breakup reduces the number of large raindrops, increases the number of small raindrops, and, as a consequence, decreases surface rain rates and considerably reduces the speed of rain formation. In addition, it was found that including breakup can lead to a more intense triggering of secondary convective cells. But a statistical comparison with observed raindrop size distributions shows that the parameterizations might systematically overestimate collisional breakup.

Corresponding author address: Dr. Axel Seifert, Deutscher Wetterdienst, GB Forschung und Entwicklung, Kaisorleistr. 42, Offenbach a. M., Germany. Email: axel.seifert@dwd.de

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  • Beard, K. V., and H. T. Ochs, 1995: Collisions between small precipitation drops. Part II: Formulas for coalescence, temporary coalescence, and satellites. J. Atmos. Sci., 52 , 3977–3996.

    • Search Google Scholar
    • Export Citation

  • Bleck, R., 1970: A fast approximative method for integrating the stochastic coalescence equation. J. Geophys. Res., 75 , 5165–5171.

    • Search Google Scholar
    • Export Citation

  • Bott, A., 1998: A flux method for the numerical solution of the stochastic collection equation. J. Atmos. Sci., 55 , 2284–2293.

  • Brown, P. S., 1997: Mass conservation considerations in analytic representation of raindrop fragment distribution. J. Atmos. Sci., 54 , 1675–1687.

    • Search Google Scholar
    • Export Citation

  • Brown, P. S., 1999: Analysis of model-produced raindrop-size distribution in the small-drop range. J. Atmos. Sci., 56 , 1382–1390.

    • Search Google Scholar
    • Export Citation

  • Costa, A. A., G. P. Almeida, and A. J. C. Sampaio, 2000: A bin-microphysics cloud model with high-order positive-definite advection. Atmos. Res., 55 , 225–255.

    • Search Google Scholar
    • Export Citation

  • Czys, R. R., 1994: Preliminary laboratory results on the coalescence of small precipitation-size drops falling freely in a refrigerated environment. J. Atmos. Sci., 51 , 3209–3220.

    • Search Google Scholar
    • Export Citation

  • Feingold, G., Z. Levin, and S. Tzivion, 1991: The evolution of raindrop spectra. Part III: Downdraft generation in an axisymmetric rainshaft model. J. Atmos. Sci., 48 , 315–330.

    • Search Google Scholar
    • Export Citation

  • Ferrier, B. S., and R. A. Houze, 1989: One-dimensional time-dependent modeling of GATE cumulonimbus convection. J. Atmos. Sci., 46 , 330–352.

    • Search Google Scholar
    • Export Citation

  • Hu, Z., and R. C. Srivastava, 1995: Evolution of raindrop size distribution by coalescence, breakup, and evaporation: Theory and observations. J. Atmos. Sci., 52 , 1761–1783.

    • Search Google Scholar
    • Export Citation

  • Joss, J., and A. Waldvogel, 1967: A raindrop spectrograph with automatic analysis. Pure Appl. Geophys., 68 , 240–246.

  • Khain, A. P., and I. L. Sednev, 1996: Simulation of precipitation formation in the eastern Mediterranean coastal zone using a spectral microphysics cloud ensemble model. Atmos. Res., 43 , 77–110.

    • Search Google Scholar
    • Export Citation

  • Khain, A., M. Ovtchinnikov, M. Pinsky, A. Pokrovsky, and H. Krugliak, 2000: Notes on the state-of-the-art numerical modeling of cloud microphysics. Atmos. Res., 55 , 159–224.

    • Search Google Scholar
    • Export Citation

  • Khain, A. P., D. Rosenfeld, and A. Pokrovsky, 2001: Simulating convective clouds with sustained supercooled liquid water down to −37.5°C using a spectral microphysics model. Geophys. Res. Lett., 28 , 3887–3890.

    • Search Google Scholar
    • Export Citation

  • Low, T. B., and R. List, 1982a: Collision, coalescence, and breakup of raindrops. Part I: Experimentally established coalescence efficiencies and fragment size distributions in breakup. J. Atmos. Sci., 39 , 1591–1606.

    • Search Google Scholar
    • Export Citation

  • Low, T. B., and R. List, 1982b: Collision, coalescence, and breakup of raindrops. Part II: Parameterization of fragment size distributions. J. Atmos. Sci., 39 , 1607–1618.

    • Search Google Scholar
    • Export Citation

  • Marshall, J. S., and W. M. K. Palmer, 1948: The distribution of raindrops with size. J. Meteor., 5 , 165–166.

  • McTaggart-Cowan, J., and R. List, 1975: Collision and breakup of water drops at terminal velocity. J. Atmos. Sci., 32 , 1401–1411.

    • Search Google Scholar
    • Export Citation

  • Pinsky, M., A. Khain, and M. Shapiro, 2001: Collision efficiency of drops in a wide range of Reynolds numbers: Effect of pressure on spectrum evolution. J. Atmos. Sci., 58 , 742–764.

    • Search Google Scholar
    • Export Citation

  • Pruppacher, H. R., and J. D. Klett, 1997: Microphysics of Clouds and Precipitation. 2d ed. Kluwer Academic, 954 pp.

  • Reisin, T. G., Y. Yin, Z. Levin, and S. Tzivion, 1998: Development of giant drops and high-reflectivity cores in Hawaiian clouds: Numerical simulations using a kinematic model with detailed microphysics. Atmos. Res., 45 , 275–297.

    • Search Google Scholar
    • Export Citation

  • Rogers, R. R., D. Baumgardner, S. A. Ethier, D. A. Carter, and W. L. Ecklund, 1993: Comparison of raindrop size distributions measured by radar wind profiler and by airplane. J. Appl. Meteor., 32 , 694–699.

    • Search Google Scholar
    • Export Citation

  • Sheppard, B. I., and P. I. Joe, 1994: Comparison of raindrop size distribution measurements by a Joss–Waldvogel disdrometer, a PMS 2DG spectrometer, and a POSS Doppler radar. J. Atmos. Oceanic Technol., 11 , 874–887.

    • Search Google Scholar
    • Export Citation

  • Simpson, J., G. V. Helvoirt, and M. McCumber, 1982: Three-dimensional simulations of cumulus congestus clouds on GATE day 261. J. Atmos. Sci., 39 , 126–145.

    • Search Google Scholar
    • Export Citation

  • Steiner, M., and A. Waldvogel, 1987: Peaks in raindrop size distributions. J. Atmos. Sci., 44 , 3127–3133.

  • Turpeinen, O., and M. K. Yau, 1981: Comparison of results from a three-dimensional cloud model with statistics of radar echoes on day 261 of GATE. Mon. Wea. Rev., 109 , 1495–1511.

    • Search Google Scholar
    • Export Citation

  • Zawadzki, I., and M. A. de Agostinho, 1988: Equilibrium raindrop size distributions in tropical rain. J. Atmos. Sci., 45 , 3452–3459.

    • Search Google Scholar
    • Export Citation
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