Experimental and computational comparison of different methods for determination of visual range
Abstract
Three visibility meters of different type have been run simultaneously over several weeks. At the same time aerosol spectra were collected using an optical counter. The visibility readings were compared under several meteorological conditions and a Junge distribution or a modified gamma - distribution has been fitted to the experimental aerosol size distribution. Using Mie's theory and the data recorded, the readings of the instruments have been compared with the computed total extinction and the values computed based on actual instrument parameters, i.e. especially the angular response in the case of two scattering type instruments. A good agreement between the observational visibilities is obtained, except under particular meteorological conditions. Computed visibilities give a generally correct prediction of the measured extinction.
- Publication:
-
In AGARD Opt. Propagation in the Atmosphere 15 p (SEE N76-29815 20-46
- Pub Date:
- May 1976
- Bibcode:
- 1976opa..agarR....B
- Keywords:
-
- Aerosols;
- Atmospheric Attenuation;
- Optical Measuring Instruments;
- Visibility;
- Atmospheric Scattering;
- Meteorological Parameters;
- Particle Size Distribution;
- Geophysics