Experimentally determined relationship between extinction coefficients and liquid water content.

Simultaneous environmental chamber measurements have been made of 10.27-microm extinction coefficients and liquid water content of droplet distributions with sizes spanning those of light to heavy fogs. The measurements yield a linear relation that is nearly independent of droplet size distribution, in agreement with recent calculated results and predictions. Liquid water content varied from 0.01 to 3.3 g/m(3), and droplet size distributions with both single and bimodal differential extinction coefficient curves were included. The spectral variation of the extinction ceofficient between 9.2 and 10.8 microm was also measured. The results are in good agreement with the variation calculated for typical droplet size distributions.