Optical Measurement of Precipitation.

Abstract

A simple optical device is used to measure changes in light intensity caused by precipitating particles as they fall through a beam of light. The intensity changes are analyzed in the amplitude and frequency domains to obtain information about precipitation. Tests conducted in snow and in rain show that the optical device can be used for characterizing precipitation with finer time resolution than conventional methods. Rain rates can be accurately monitored; however, errors in snow rates can be as high as a factor of two. Number flux measurements suggest that periodic trends may exist during snow and rain. Power spectra of the intensity changes show that spectral signatures exist for different types of precipitation. Keywords: Optical measurements; Precipitation; Rain; Snow. (jhd)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1989
Accession Number
ADA214357

Entities

People

  • Gary Koh

Organizations

  • Cold Regions Research and Engineering Laboratory

Tags

DTIC Thesaurus Topics

  • Amplitude
  • Frequency
  • Frequency Domain
  • Intensity
  • Measurement
  • Particles
  • Power Spectra
  • Precipitation
  • Spectra

Readers

  • Aerosol Science/Aerosol Physics
  • Atmospheric Science/Meteorology