High resolution computer calculation of optical transmittance at sea level over Monterey
MetadataShow full item record
Computer programs have been developed for calculation of the molecular absorption and aerosol extinction for horizontal path propagation of radiation in the wavelength range above 0.55 µm. The AFCRL line parameters compilation is used as input data with local weather conditions for the Monterey Bay and model of typical aerosol size distribution from Shettle and Fenn. Wind speed and relative humidity are included in the form developed by Wells, Gal and Munn. Infinite resolution computations have been carried out for 1.06, 3.8 and 10.6 µm and results tabulated for monthly and yearly average weather conditions on Monterey Bay. Bandwidth-averaged spectral transmittances have been calculated at 0.01 cm-l and 0.5 cm-l resolution for the same conditions. Comparisons with previously published data show agreement to 1.8% with maritime model aerosol Mie-scattering calculations by Selby using LOWTRAN III B [Ref. 12]. Analysis of sensitivity to changes of pressure and temperature for the 3.8 µm range showed only small effects of these parameters. However a change in water vapor partial pressure results in a 0.75%/mbar change in transmittance in the 3.8 µm region.
Approved for public release; distribution is unlimited