A Vertical Structure Algorithm for Low Visibility/Low Stratus Conditions.

Abstract : Based on data describing the vertical structure in haze and fog, and on empirical parameterizations of that data, an algorithm of simple analytical form has been developed that describes the vertical structure for low visibility/low ceiling conditions. The algorithm describes the vertical structure fo the visible extinction coefficient and liquid water content for two regimes: (1) the case of thick fogs and low stratus clouds, where the liquid water content is governed primarily by the wet adiabatic lapse rate; and (2) the case of hazes and thin fogs, where the vertical structure is determined by advection, radiative and conductive cooling, and hydration processes below and at saturation. (Author)