Article Type:
Research Article

Discrimination of Bird and Insect Radar Echoes in Clear Air Using High-Resolution Radars

William J. Martin Center for Analysis and Prediction of Storms, University of Oklahoma, Norman, Oklahoma

Search for other papers by William J. Martin in
Current site
Google Scholar
PubMed Close
and
Alan Shapiro Center for Analysis and Prediction of Storms, and School of Meteorology, University of Oklahoma, Norman, Oklahoma

Search for other papers by Alan Shapiro in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Jul 2007
DOI:
https://doi.org/10.1175/JTECH2038.1
Page(s):
1215–1230
Restricted access

Abstract

The source of clear-air reflectivity from operational and research meteorological radars has been a subject of much debate and study over the entire history of radar meteorology. Recent studies have suggested that bird migrations routinely contaminate wind profiles obtained at night, while historical studies have suggested insects as the main source of such nocturnal clear-air echoes. This study analyzes two cases of nocturnal clear-air return using data from operational Weather Surveillance Radar-1988 Doppler (WSR-88D) and X- and W-band research radars. The research radars have sufficient resolution to resolve the echo as point targets in some cases. By examining the radar cross section of the resolved point targets, and by determining the target density, it is found for both cases of nocturnal clear-air echoes that the targets are almost certainly insects. The analysis of the dependence of the echo strength on radar wavelength also supports this conclusion.

Corresponding author address: Dr. William Martin, Center for Analysis and Prediction of Storms, National Weather Center, Suite 2500, 120 David L. Boren Blvd., Norman, OK 73072. Email: wjmartin@ou.edu

Abstract

The source of clear-air reflectivity from operational and research meteorological radars has been a subject of much debate and study over the entire history of radar meteorology. Recent studies have suggested that bird migrations routinely contaminate wind profiles obtained at night, while historical studies have suggested insects as the main source of such nocturnal clear-air echoes. This study analyzes two cases of nocturnal clear-air return using data from operational Weather Surveillance Radar-1988 Doppler (WSR-88D) and X- and W-band research radars. The research radars have sufficient resolution to resolve the echo as point targets in some cases. By examining the radar cross section of the resolved point targets, and by determining the target density, it is found for both cases of nocturnal clear-air echoes that the targets are almost certainly insects. The analysis of the dependence of the echo strength on radar wavelength also supports this conclusion.

Corresponding author address: Dr. William Martin, Center for Analysis and Prediction of Storms, National Weather Center, Suite 2500, 120 David L. Boren Blvd., Norman, OK 73072. Email: wjmartin@ou.edu

Save
Cover Journal of Atmospheric and Oceanic Technology
Journal of Atmospheric and Oceanic Technology

  • Bachmann, S., and Zrnić D. S. , 2005: Spectral polarimetry for identifying and separating mixed biological scatterers. Preprints, 32d Conf. on Radar Meteorology, Albuquerque, NM, Amer. Meteor. Soc., CD-ROM, P9R.5.

  • Battan, L. J., 1973: Radar Observations of the Atmosphere. University of Chicago Press, 324 pp.

  • Berry, R. E., and Taylor L. R. , 1968: High altitude migration of aphids in maritime and continental climates. J. Anim. Ecol., 37 , 713–722.

  • Blake, L. V., 1970: Prediction of radar range. Radar Handbook, M. I. Skolnik, Ed., McGraw-Hill, 2.1–2.73.

  • Bluestein, H. B., and Pazmany A. L. , 2000: Observations of tornadoes and other convective phenomena with a mobile, 3-mm wavelength Doppler radar: The spring 1999 field experiment. Bull. Amer. Meteor. Soc., 81 , 2939–2951.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Browning, K. A., and Atlas D. , 1966: Velocity characteristics of some clear-air dot angels. J. Atmos. Sci., 23 , 592–604.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Collins, W. G., 2001: The quality control of velocity azimuth display (VAD) winds at the National Centers for Environmental Prediction. Preprints, 11th Symp. on Meteorological Observations and Instrumentation, Albuquerque, NM, Amer. Meteor. Soc., CD-ROM, 9.2.

  • Crawford, A. B., 1949: Radar reflections in the lower atmosphere. Proc. IRE, 37 , 404–405.

  • Crum, T. D., Alberty R. L. , and Burgess D. W. , 1993: Recording, archiving, and using WSR-88D data. Bull. Amer. Meteor. Soc., 74 , 645–653.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Drake, V. A., 1984: The vertical distribution of macro-insects migrating in the nocturnal boundary layer: A radar study. Bound.-Layer Meteor., 28 , 353–374.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Drake, V. A., 1985: Radar observations of moths migrating in a nocturnal low-level jet. Ecol. Entomol., 10 , 259–265.

  • Eastwood, E., 1967: Radar Ornithology. Methuen & Co., 278 pp.

  • Elder, F. C., 1957: Some persistent “ring” angels on high-powered radar. Proc. Sixth Weather Radar Conf., Cambridge, MA, Amer. Meteor. Soc., 281–290.

  • Friend, A. W., 1939: Continuous determination of air-mass boundaries by radio. Bull. Amer. Meteor. Soc., 20 , 202–205.

  • Gauthreaux, S. A., and Belser C. G. , 1998: Displays of bird movements on the WSR-88D: Patterns and quantification. Wea. Forecasting, 13 , 453–464.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Gauthreaux, S. A., Mizrahi D. S. , and Belser C. G. , 1998: Bird migration and bias of WSR-88D wind estimates. Wea. Forecasting, 13 , 465–481.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Geerts, B., and Miao Q. , 2005a: The use of millimeter Doppler radar echoes to estimate vertical air velocities in the fair-weather convective boundary layer. J. Atmos. Oceanic Technol., 22 , 225–246.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Geerts, B., and Miao Q. , 2005b: A simple numerical model of the flight behavior of small insects in the atmospheric convective boundary layer. Environ. Entomol., 34 , 251–272.

    • Search Google Scholar
    • Export Citation

  • Gossard, E. E., 1990: Radar research on the atmospheric boundary layer. Radar in Meteorology, D. Atlas, Ed., Amer. Meteor. Soc., 477–527.

    • Search Google Scholar
    • Export Citation

  • Gunn, K. L. S., and East T. W. R. , 1954: The microwave properties of precipitation particles. Quart. J. Roy. Meteor. Soc., 80 , 522–545.

  • Hardy, K. R., and Glover K. M. , 1966: 24 hour history of radar angel activity at three wavelengths. Proc12th Conf. on Radar Meteorology, Norman, OK, Amer. Meteor. Soc., 264–268.

  • Hardy, K. R., and Katz I. , 1969: Probing the atmosphere with high power, high resolution radars. Proc. IEEE, 57 , 468–480.

  • Hardy, K. R., and Gage K. S. , 1990: The history of radar studies of the clear atmosphere. Radar in Meteorology, D. Atlas, Ed., Amer. Meteor. Soc., 130–142.

    • Crossref
    • Export Citation

  • Jain, M., Eilts M. , and Hondl K. , 1993: Observed differences of the horizontal wind derived from Doppler radar and a balloon-borne atmospheric sounding system. Preprints, Eighth Symp. on Meteorological Observations and Instrumentation, Anaheim, CA, Amer. Meteor. Soc., 189–194.

  • Jungbluth, K., Belles J. , and Schumacher M. , 1995: Velocity contamination of WSR-88D and wind profiler data due to migrating birds. Preprints, 27th Conf. on Radar Meteorology, Vail, CO, Amer. Meteor. Soc., 666–668.

  • Klazura, G. E., and Imy D. A. , 1993: A description of the initial set of analysis products available from the NEXRAD WSR-88D system. Bull. Amer. Meteor. Soc., 74 , 1293–1311.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Kropfli, R. A., Katz I. , Konrad T. G. , and Dobson E. B. , 1968: Simultaneous radar reflectivity measurements and refractive index spectra in the clear atmosphere. Radio Sci., 3 , 991–994.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Lane, J. A., and Meadows R. W. , 1963: Simultaneous radar and refractometer soundings of the troposphere. Nature, 197 , 35–36.

  • Lang, T. J., Rutledge S. A. , and Stith J. L. , 2004: Observations of quasi-symmetric echo patterns in clear air with the CSU-CHILL polarimetric radar. J. Atmos. Oceanic Technol., 21 , 1182–1189.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Larkin, R. P., 1991: Flight speeds observed with radar, a correction: Slow “birds” are insects. Behav. Ecol. Sociobiol., 29 , 221–224.

  • Lhermitte, R., 1990: Attenuation and scattering of millimeter wavelength radiation by clouds and precipitation. J. Atmos. Oceanic Technol., 7 , 464–479.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Liu, S., Xu Q. , and Zhang P. , 2005: Identifying Doppler velocity contamination caused by migrating birds. Part II: Bayes identification and probability tests. J. Atmos. Oceanic Technol., 22 , 1114–1121.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Lowery G. H. Jr., , and Newman R. J. , 1966: A continentwide view of bird migration on four nights in October. Auk, 83 , 547–586.

  • Martin, W. J., 2003: Measurements and Modeling of the Great Plains Low-Level Jet. Ph.D. dissertation, University of Oklahoma, 243 pp.

  • Martin, W. J., and Shapiro A. , 2005: Impact of radar tilt and ground clutter on wind measurements in clear air. J. Atmos. Oceanic Technol., 22 , 649–663.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Miller, P. A., Barth M. F. , Smart J. R. , and Benjamin L. A. , 1997: The extent of bird contamination in the hourly winds measured by the NOAA profiler network: Results before and after implementation of the new bird contamination quality control check. Preprints, First Symp. on Integrated Observing Systems, Long Beach, CA, Amer. Meteor. Soc., 138–144.

  • Mueller, E. A., 1983: Differential reflectivity of birds and insects. Preprints, 21st Conf. on Radar Meteorology, Edmonton, AB, Canada, Amer. Meteor. Soc., 465–466.

  • O’Bannon, T., 1995: Anomalous WSR-88D wind profiles—Migrating birds? Preprints, 27th Conf. on Radar Meteorology, Vail, CO, Amer. Meteor. Soc., 663–665.

  • Pekour, M. S., and Coulter R. L. , 1999: A technique for removing the effect of migrating birds in 915-MHz wind profiler data. J. Atmos. Oceanic Technol., 16 , 1941–1948.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Probert-Jones, J. R., 1962: The radar equation in meteorology. Quart. J. Roy. Meteor. Soc., 88 , 485–495.

  • Reynolds, D. R., Chapman J. W. , Edwards A. S. , Smith A. D. , Wood C. R. , Barlow J. F. , and Woiwod I. P. , 2005: Radar studies of the vertical distribution of insects migrating over southern Britain: The influence of temperature inversions on nocturnal layer concentrations. Bull. Entomol. Res., 95 , 259–274.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Riley, J. R., 1975: Collective orientation in night-flying insects. Nature, 253 , 113–114.

  • Riley, J. R., 1985: Radar cross section of insects. Proc. IEEE, 73 , 228–232.

  • Riley, J. R., 1989: Remote sensing in entomology. Annu. Rev. Entomol., 34 , 247–271.

  • Russell, R. W., and Wilson J. W. , 1997: Radar-observed “fine lines” in the optically clear boundary layer: Reflectivity contributions from aerial plankton and its predators. Bound.-Layer Meteor., 82 , 235–262.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Schaefer, G. W., 1976: Radar observations of insect flight. Insect Flight, R. C. Rainey, Ed., John Wiley & Sons, 157–197.

  • Shamoun-Baranes, J., van Loon E. , van Gasteren H. , van Belle J. , Bouten W. , and Buurma L. , 2006: A comparative analysis of the influence of weather on the flight altitudes of birds. Bull. Amer. Meteor. Soc., 87 , 47–61.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Silverman, R. A., 1956: Turbulent mixing theory applied to radio scattering. J. Appl. Phys., 27 , 699–705.

  • Tatarski, V. I., 1961: Wave Propagation in a Turbulent Medium. McGraw-Hill, 285 pp. (Translated from Russian by R. A. Silverman.).

  • Van de Kamp, D. W., Ralph F. M. , Barth M. F. , Miller P. A. , Smart J. R. , and Benjamin L. A. , 1997: The new bird contamination quality control check applied to hourly winds from NOAA’s profiler network. Preprints, 28th Conf. on Radar Meteorology, Austin, TX, Amer. Meteor. Soc., 131–132.

  • Vaughn, C. R., 1985: Birds and insects as radar targets: A review. Proc. IEEE, 73 , 205–227.

  • Wilczak, J. M., and Coauthors, 1995: Contamination of wind profiler data by migrating birds: Characteristics of corrupted data and potential solutions. J. Atmos. Oceanic Technol., 12 , 449–467.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Wilson, J. W., Weckwerth T. M. , Vivekanandan J. , Wakimoto R. M. , and Russell R. W. , 1994: Boundary layer clear-air radar echoes: Origin of echoes and accuracy of derived winds. J. Atmos. Oceanic Technol., 11 , 1184–1206.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Wiscombe, W. J., 1979: Mie scattering calculations: Advances in technique and fast, vectorspeed computer codes. NCAR Tech. Note NCAR/TN-140+STR, 64 pp.

  • Wiscombe, W. J., 1980: Improved Mie scattering algorithms. Appl. Opt., 19 , 1505–1509.

  • Wurman, J., 2001: The DOW mobile multiple-Doppler network. Preprints, 30th Int. Conf. on Radar Meteorology, Munich, Germany, Amer. Meteor. Soc., 95–97.

  • Wurman, J., Straka J. , Rasmussen E. , Randall M. , and Zahrai A. , 1997: Design and deployment of a portable, pencil-beam, pulsed 3-cm Doppler radar. J. Atmos. Oceanic Technol., 14 , 1502–1512.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Zhang, P., Liu S. , and Xu Q. , 2005a: Identifying Doppler velocity contamination caused by migrating birds. Part I: Feature extraction and quantification. J. Atmos. Oceanic Technol., 22 , 1105–1113.

    • Crossref
    • Search Google Scholar
    • Export Citation

  • Zhang, P., Ryzhkov A. V. , and Zrnić D. , 2005b: Observations of insects and birds with a polarimetric prototype of the WSR-88D radar. Preprints, 32d Conf. on Radar Meteorology, Albuquerque, NM, Amer. Meteor. Soc., CD-ROM, 9R.6.

  • Zrnić, D. S., and Ryzhkov A. V. , 1998: Observations of insects and birds with a polarimetric radar. IEEE Trans. Geosci. Remote Sens., 36 , 661–668.

  • Zrnić, D. S., and Ryzhkov A. V. , 1999: Polarimetry for weather surveillance radars. Bull. Amer. Meteor. Soc., 80 , 389–406.

    • Crossref
    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1675 830 131
PDF Downloads 807 155 4