Atmospheric aerosols, humidity, and visibility

Abstract

Aerosol properties such as particle size distribution, particle mass, and the chemical composition in the optical size range (0.1-0.2 microns in diameter), where they interact most effectively with visible light, are discussed on a physical and quantitative basis with reference to visibility reduction. It is shown that the degradation of visual range by aerosol particles is due to the accumulation mode, except in dust storms and fog relative humidity has predictable and measurable effects on visual range, which are small if relative humidity is less than 70%.