Paper
15 May 1981 Three-Wavelength Lidar Method To Measure Mass Concentration In An Unknown Pollutant Cloud
S. Rafi Ahmad
Author Affiliations +
Proceedings Volume 0236, 1980 European Conf on Optical Systems and Applications; (1981) https://doi.org/10.1117/12.959002
Event: 1980 European Conference on Optical Systems and Applications, 1980, Utrecht, Netherlands
Abstract
The mass concentration in a pollutant cloud can be estimated from the normalized range-corrected LIDAR signal S(R) if the clear-air mass concentration and the parameter Ω defined as the ratio of some weighted (by the product of the size distribution function and the square of the radius) average of the total scattering efficiency to the volume to surface average radius, are known. The ratio Ω can be calculated by numerically solving the LIDAR equation for three different wavelengths in terms of the observed quantities S(R,λ), the known values of the λ's and an assumed value of the refractive index m. In the present analyses, S-functions are simulated for log-normal size distributions with different values of the standard deviation. For simplicity spatially uniform number density is assumed so that only two-wavelength calculations are needed. Assumed mass concentrations (for different widths of the size distribution) are compared with those calculated using the modified LIDAR equation. The results show that the validity of the method is limited by the width of the size distribution and the product (R-Ro)N where (R-Ro) is the probed range inside the cloud and N is the number density.
© (1981) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
S. Rafi Ahmad "Three-Wavelength Lidar Method To Measure Mass Concentration In An Unknown Pollutant Cloud", Proc. SPIE 0236, 1980 European Conf on Optical Systems and Applications, (15 May 1981); https://doi.org/10.1117/12.959002
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Scattering

LIDAR

Clouds

Particles

Refractive index

Absorption

Laser scattering

RELATED CONTENT


Back to Top