Reflectivity and Attenuation at Millimeter to Infrared Wavelengths for Advection Fogs at Four Locations

Abstract

Recent drop size distribution data from four advection fog sites are reanalyzed for the purpose of predicting millimeter-wave and infrared to visible wavelength reflectivity and attenuation coefficients in such fogs. A gamma drop size distribution model is shown to be an adequate fit to measured distributions of typical fog drop diameters. Conclusions are drawn with respect to the relationships between the reflectivity and the attenuation to the liquid water content. A possible method is outlined for using ground-based measurement of liquid water content for the purpose of predicting arbitrary slant-path reflectivity and attenuation at the smaller wavelengths.