Dry deposition and desorption of toxic gases to and for snow surfaces

摘要

A model describing toxic gas deposition to and desorption form a snow surface is presented. The model is based on the assumption that the deposition is caused by an adsorption of the toxic Gas to small amounts of liquid water, which exist in the snow at temperatures equal to or below 0 dig C. It includes molecular diffusion in the snow, partition between gas and solution by use of Henry's law, drainage flow in melting snow and decomposition of agent. The interface to the Atmosphere is defined by the flux to and from the surface with help of the aerodynamic resistance And the resistance in the viscous sub-layer. Deposition velocities to snow for some air pollutants Are reviewed.