Abstract
Some computations are made of submillimeter wave extinction in clouds and fogs using recent spectrometric results of the optical properties of water. At wavelengths > 1000μ an approximate formula is adequate in which extinction is proportional to cloud water content. At 2000 and 1000μ the extinction is 6.5 and 15.2 dB km−1 per gm m−3, respectively. Between 200 and 1000μ additional extinction occurs due to large droplets of diameters >20μ. Extinction for a typical fog distribution is computed and is found to be 41.1 dB km−1 per gm m−3 at 337 μ and 92.8 dB km−1 per gm m−3 at 200μ. Comparisons with experimental data at 1200 and 337μ shows qualitative agreement, but insufficient data on the composition of the clouds and fogs investigated precludes accurate comparison.
