An Examination of a Simulated Microburst Flow as Sensed by a Single Doppler Radar

Abstract

The range and azimuthal limitations of a single Doppler radar in accurately determining velocity-based microburst parameters were studied. A vortex ring model was developed to simulate the microburst flow. The simulated velocities were vertically averaged over the lowest 500 meters of the flow using a Gaussian-squared weighting distribution. Smoothed values of radial shear parameters were examined for microbursts centered less than 30 km from a single Doppler radar; smoothing effects were minimal for azimuths of less than five degrees. Unsmoothed radial shear parameters were also compared as a function of azimuth, range, and arc length for microbursts centered from 15 km to 150 km from a Doppler radar. Detected radial shear decreases with increasing range and azimuth due to beam spreading. For a one-degree beam, the planned NEXRAD sampling rate, the difference in radial shear for a maximum 0.5-degree offset between 15-km and 150-km microbursts is 18%, creating non-existent fluctuations. For short arc lengths, the differences in radial shear parameters are small; they increase for longer arc lengths but the shear magnitudes are small.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1988
Accession Number
ADA196381

Entities

People

  • Eleanor L. Smith

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aircrafts
  • Boundary Layer
  • Clutter
  • Doppler Radar
  • Elevation
  • Flow Fields
  • Frequency
  • Frequency Shift
  • Ground Clutter
  • Layers
  • Measurement
  • Meteorological Radar
  • Meteorology
  • Radar
  • Sampling
  • Three Dimensional
  • United States

Readers

  • Approximation Theory.
  • Atmospheric Science/Meteorology
  • Radar Systems Engineering.