Airborne Measurements of Optical Atmospheric Properties, Summary and Review III

This report summarizes a three year period devoted primarily to collection and evaluation of optical atmospheric data describing the western European environment. Five field expeditions were made between April 1976 and September 1978. They were conducted as a cooperative, but independent effort associated with the NATO Research Study Group 8 of Panel IV, AC243 and their Program OPAQUE. Measurements were made in six representative geographical areas during each of the four seasons, Summer, Fall, Winter and Spring. Optical measurements were made in four regions within the visual spectrum as follows: two moderately narrow bands having mean wavelengths of 478 and 664 nanometers, one slightly wider band at 765 nanometers and one relatively broad band representing the photopic response having a mean wavelength of 557 nanometers. The daytime optical measurements included total volume scattering coefficient, sky and terrain radiances, and both upwelling and downwelling irradiances. Simultaneous meteorological measurements included temperature, dewpoint temperature and atmospheric pressure. The optical atmospheric properties derived from these data and presented in reports typified by AFGL-TR-76-0188 and AFGL-TR-78-0168 are reviewd as are their methods of derivation and validation. The methods of data collection and processing are summarized and reviewed as is the overall resulting data bank. Examples related to the use of the data are included as well as recommendations for further data study and interpretation. (Author)