High-Frequency Single-Board Doppler Minisodar for Precipitation Measurements. Part I: Rainfall and Hail

Shixuan Pang Max-Planck-Institut für Meteorologie, Hamburg, Germany

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Hartmut Graßl Max-Planck-Institut für Meteorologie, and Meteorologisches Institut, Universität Hamburg, Hamburg, Germany

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Abstract

A high-frequency Doppler sodar for precipitation measurements has been developed. Such a Doppler sodar (6–20 kHz) can almost always measure precipitation and turbulence spectra simultaneously. Therefore, the mean vertical wind and spectral broadening effects can be directly removed. As the acoustic refractive indices for ice and liquid water are almost the same, the acoustic retrieval of precipitation can also be applied to rain with small hail (e.g., diameter D < 10 mm) or large hail, but for the latter, neglecting the effects of different orientations and shapes of hailstones.

The authors’ single-board minisodar is based on the digital signal processing (DSP) technique. The first prototype has been continuously operated at a coastal weather station since 25 October 2002. For stratiform rain events, the minisodar showed good agreement with a Joss–Waldvogel disdrometer and an optical rain gauge. However, for convective heavy showers, the minisodar always observed higher rain rates.

The continuous, nonattended automatic operation of the minisodar has shown its capability for all kinds of precipitation measurements. The retrieval of precipitation rates for snow and graupel will be provided in a subsequent paper.

Corresponding author address: Dr. Shixuan Pang, Max-Planck-Institut für Meteorologie, Bundesstrasse 55, D-20146 Hamburg, Germany. Email: pang@dkrz.de

Abstract

A high-frequency Doppler sodar for precipitation measurements has been developed. Such a Doppler sodar (6–20 kHz) can almost always measure precipitation and turbulence spectra simultaneously. Therefore, the mean vertical wind and spectral broadening effects can be directly removed. As the acoustic refractive indices for ice and liquid water are almost the same, the acoustic retrieval of precipitation can also be applied to rain with small hail (e.g., diameter D < 10 mm) or large hail, but for the latter, neglecting the effects of different orientations and shapes of hailstones.

The authors’ single-board minisodar is based on the digital signal processing (DSP) technique. The first prototype has been continuously operated at a coastal weather station since 25 October 2002. For stratiform rain events, the minisodar showed good agreement with a Joss–Waldvogel disdrometer and an optical rain gauge. However, for convective heavy showers, the minisodar always observed higher rain rates.

The continuous, nonattended automatic operation of the minisodar has shown its capability for all kinds of precipitation measurements. The retrieval of precipitation rates for snow and graupel will be provided in a subsequent paper.

Corresponding author address: Dr. Shixuan Pang, Max-Planck-Institut für Meteorologie, Bundesstrasse 55, D-20146 Hamburg, Germany. Email: pang@dkrz.de

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  • Atlas, D., Saivastava R. C. , and Sekhon R. S. , 1973: Doppler radar characteristics of precipitation at vertical incidence. Rev. Geophys. Space Phys., 11 , 135.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Aydin, K., Seliga A. , and Bringi V. N. , 1984: Differential radar scattering properties of model hail and mixed phase hydrometeors. Radio Sci., 19 , 5866.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Aydin, K., Zhao Y. , Seliga A. , and Bringi V. N. , 1990: A differential reflectivity radar hail measurement technique: Observations during the Denver hailstorm of 13 June 1984. J. Atmos. Oceanic Technol., 7 , 104113.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Balakrishnan, N., and Zrnić D. S. , 1990: Estimation of rain and hail rates in mixed-phase precipitation. J. Atmos. Sci., 47 , 565583.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Battan, L. J., and Bohren C. F. , 1986: Attenuation of microwaves by spherical hail. J. Climate Appl. Meteor., 25 , 11551159.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Battan, L. J., Browning S. R. , and Herman B. M. , 1970: Attenuation of microwaves by wet ice spheres. J. Appl. Meteor., 9 , 832834.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bohne, A. R., 1982: Radar detection of turbulence in precipitation environments. J. Atmos. Sci., 39 , 18171837.

  • Bohren, C. F., and Battan L. J. , 1980: Radar backscattering by inhomogeneous precipitation particles. J. Atmos. Sci., 37 , 18211827.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bohren, C. F., and Battan L. J. , 1982: Radar backscattering of microwaves by spongy ice spheres. J. Atmos. Sci., 39 , 26232628.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bradley, S. G., 1996a: A high-frequency Doppler acoustic precipitation radar. Proc. Eight Int. Symp. Acoustic Remote Sensing, Moscow, Russia, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 3.13–3.18.

  • Bradley, S. G., 1996b: High-frequency acoustic observations of single rain drops. Proc. Eighth Int. Symp. Acoustic Remote Sensing, Moscow, Russia, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 3.19–3.21.

  • Bradley, S. G., 1997: Acoustic radar studies of rain microphysics. J. Atmos. Oceanic Technol., 14 , 547553.

  • Cheng, L., and English M. , 1983: A relationship between hailstone concentration and size. J. Atmos. Sci., 40 , 204213.

  • Chylek, P. B., Gupta R. D. , Knight N. C. , and Knight C. A. , 1984: Distribution of water in hailstones. J. Climate Appl. Meteor., 23 , 14691472.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Coulter, R. L., and Martin T. J. , 1986: Results from a high power, high frequency sodar. Atmos. Res., 20 , 257270.

  • Coulter, R. L., Martin T. J. , and Weckwerth T. M. , 1989: Minisodar measurements of rain. J. Atmos. Oceanic Technol., 6 , 369377.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Duvernoy, J., and Gaumet J. L. , 1996: Precipitation hydrometeor characterization by a CW Doppler radar. J. Atmos. Oceanic Technol., 13 , 620629.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gossard, E. E., 1988: Measuring drop-size distributions in clouds with a clear-air-sensing Doppler radar. J. Atmos. Oceanic Technol., 5 , 640649.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gossard, E. E., and Strauch R. G. , 1990: The retrieval of dropsize distributions in water clouds from ground-based clear-air-sensing Doppler radar observations. Meteor. Rundsch., 42 , 174180.

    • Search Google Scholar
    • Export Citation
  • Gossard, E. E., Strauch R. G. , and Rogers R. R. , 1990: Evolution of drop-size distributions in liquid precipitation observed by ground-based Doppler radar. J. Atmos. Oceanic Technol., 7 , 815828.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Grassl, H., Pang S. X. , and Mo F. Y. , 2000: A minisodar on a single DSP board. Proc. 10th Int. Symp. Acoustic Remote Sensing, Auckland, New Zealand, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 39–43.

  • Grassl, H., Pang S. X. , and Mo F. Y. , 2002: A comparison of several high frequency Doppler-sodar configurations. Proc. 11th Int. Symp. Acoustic Remote Sensing, Rome, Italy, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 123–126.

  • Gunn, R., and Kinzer G. D. , 1949: The terminal velocity of fall for water droplets in stagnant air. J. Meteor., 6 , 243248.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hildebrand, P. H., and Sekhon R. S. , 1974: Objective determination of the noise level in Doppler spectra. J. Appl. Meteor., 13 , 808811.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kinsler, L. E., and Frey A. R. , 1962: Fundamentals of Acoustics. John Wiley & Sons, 524 pp.

  • Lee, A. C. L., 1988: The influence of vertical air velocity on the remote microwave measurement of rain. J. Atmos. Oceanic Technol., 5 , 727735.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • List, R., 1959: Wachstum von Eis-Wassergemischen im Hagelversuchskanal. Helv. Phys. Acta, 32 , 293296.

  • List, R., Donaldson N. R. , and Stewart R. E. , 1987: Temporal evolution of drop spectra to collisional equilibrium in steady and pulsating rain. J. Atmos. Sci., 44 , 362372.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Little, C. G., 1972: On the detectability of fog, cloud, rain and snow by acoustic echo-sounding methods. J. Atmos. Sci., 29 , 748755.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Longtin, D. R., Bohren C. F. , and Battan L. J. , 1987: Radar backscattering by large, spongy ice oblate spheroids. J. Atmos. Oceanic Technol., 4 , 355358.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Macklin, W. C., 1961: Accretion in mixed clouds. Quart. J. Roy. Meteor. Soc., 87 , 413424.

  • Matrosov, S. Y., 1992: Radar reflectivity in snowfall. IEEE Trans. Geosci. Remote Sens., 30 , 454461.

  • McFarquhar, G. M., and List R. , 1993: The effect of curve fits for the disdrometer calibration on raindrop spectra, rainfall rate, and radar reflectivity. J. Appl. Meteor., 32 , 774782.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mursch-Radlgruber, E., and Wolfe D. E. , 1993: Mobile high-frequency mini-SODAR and its potential for boundary-layer studies. Appl. Phys., B57 , 5763.

    • Search Google Scholar
    • Export Citation
  • Nystuen, J. A., Proni J. R. , Black P. G. , and Wilkerson J. C. , 1996: A comparison of automatic rain gauges. J. Atmos. Oceanic Technol., 13 , 6273.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pang, S. X., and Grassl H. , 1994: Precipitation retrieval from high frequency SODAR measurements. Preprints, Climate Parameters in Radiowave Propagation Prediction (CLIMPAMA)’94, Moscow, Russia, NIIR, 2.7.1–2.7.4.

  • Pang, S. X., and Grassl H. , 1995: Sodar for precipitation measurements. Rep. 160, Max-Planck-Institut für Meteorologie, 46 pp.

  • Pang, S. X., Grassl H. , and Mo F. Y. , 2000: Additions to our minisodar-disdrometer: On-line precipitation retrieval by deconvolution of Doppler spectra and the application of an acoustic filter. Proc. 10th Int. Symp. Acoustic Remote Sensing, Auckland, New Zealand, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 228–232.

  • Pang, S. X., Grassl H. , and Mo F. Y. , 2002: Special aspects of a high-frequency-minisodar for precipitation measurements. Proc. 11th Int. Symp. Acoustic Remote Sensing, Rome, Italy, International Society of Acoustic Remote Sensing of the Atmosphere and Oceans, 445–448.

  • Rajopadhyaya, D. K., May P. T. , and Vincet R. A. , 1993: A general approach to the retrieval of raindrop size distributions from wind profiler Doppler spectra: Modeling results. J. Atmos. Oceanic Technol., 10 , 710717.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ralph, F. M., Neiman P. J. , and Ruffieux D. , 1996: Precipitation identification from radar wind profiler spectral moment data: Vertical velocity histograms, velocity variance, and signal power–vertical velocity correlations. J. Atmos. Oceanic Technol., 13 , 545559.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sato, T., Doji H. , Iwai H. , Kimura I. , Fukao S. , Yamamoto M. , Tsuda T. , and Kato S. , 1990: Computer processing for deriving drop-size distributions and vertical air velocities from VHF Doppler radar spectra. Radio Sci., 25 , 961973.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sheppard, B. E., 1990a: Measurement of raindrop size distributions using a small Doppler radar. J. Atmos. Oceanic Technol., 7 , 255268.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sheppard, B. E., 1990b: Effect of irregularities in the diameter classification of raindrops by the Joss–Waldvogel disdrometer. J. Atmos. Oceanic Technol., 7 , 180183.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sheppard, B. E., and Joe P. I. , 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 , 874887.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Spilhaus, A. F., 1948: Raindrop size, shape, and falling speed. J. Meteor., 5 , 108110.

  • Steiner, M., and Waldvogel A. , 1987: Peaks in raindrop size distributions. J. Atmos. Sci., 44 , 31273133.

  • Ulbrich, C. W., 1992: Algorithm for determination of rainfall integral parameters using reflectivity factor and mean Doppler fall speed at vertical incidence. J. Atmos. Oceanic Technol., 9 , 120128.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ulbrich, C. W., and Atlas D. , 1982: Hail parameters: A comprehensive digest. J. Appl. Meteor., 21 , 2242.

  • Wakasugi, W., Mizutani A. , and Matsuo M. , 1986: A direct method for deriving drop-size distribution and vertical air velocity from VHF Doppler radar spectra. J. Atmos. Oceanic Technol., 3 , 623629.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wakasugi, W., Mizutani A. , and Matsuo M. , 1987: Further discussion on deriving drop-size distribution and vertical air velocities directly from VHF Doppler radar spectra. J. Atmos. Oceanic Technol., 4 , 170179.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Weill, A., Klapisz C. , and Baudin F. , 1986: The CRPE minisodar: Applications in micrometeorology and in physics of precipitations. Atmos. Res., 20 , 317333.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wilson, J. W., 1970: Integration of radar and raingage data for improved rainfall measurement. J. Appl. Meteor., 9 , 489497.

    • Crossref
    • Search Google Scholar
    • Export Citation
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