Aerosol size distributions: remote determination from air-borne measurements of the solar aureole

Journal Article · Thu Apr 01 04:00:00 EST 1976 · Appl. Opt.; (United States)

DOI:https://doi.org/10.1364/AO.15.000980· OSTI ID:7225401

Twitty, J T; Parent, R J; Weinman, J A; Eloranta, E W

Aerosol size distributions were determined remotely using an airborne scanning photometer. This was the first data obtained from an airborne instrument that measures the aureole. The photometer consists of a sunshade, optics and a large dynamic range photodetector-amplifier system that scans about the vertical, recording both the direct attenuated solar beam and the diffuse sky radiance in the almucantar of the sun at an effective wavelength of 0.54 ..mu..m. The inversion of the measured radiances determined aerosol radii from approximately 0.2 to 8.0 ..mu..m. Data were taken during flights in May 1973 over western Lake Superior and southwestern Wisconsin. Inverted aerosol size distributions are compared with results obtained by other methods. Comparisons indicate that the typical characteristics of tropospheric hazes are found in the size distributions obtained from the scanning photometer data. These include the approximate power law behavior of the number distribution and the deviations from the power law. The consistency between the backscatter coefficient profile measured by the lidar system on May 30 with that calculated from the size distribution indicates that scanning photometer measurements of the aureole can be used to calibrate lidar backscatter returns and to separate the scattering coefficient from the phase function at 180/sup 0/.

• Research Organization: Univ. of Wisconsin, Madison
• OSTI ID: 7225401
• Journal Information: Appl. Opt.; (United States), Journal Name: Appl. Opt.; (United States) Vol. 15:4; ISSN APOPA
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140100* -- Solar Energy-- Resources & Availability
AEROSOLS
COLLOIDS
DISPERSIONS
EARTH ATMOSPHERE
EQUIPMENT
MEASURING INSTRUMENTS
MEASURING METHODS
PARTICLE SIZE CLASSIFIERS
PHOTOMETERS
SIZE
SOLAR FLUX
SOLS