New column simulations for the Viking landers: Winds, fog, frost, adsorption?

In simulations without adsorption frost forms early and it grows thick. At VL2 fog now forms earlier and the jump in optical depth is larger than observed. At the drier VL1 fog still forms nearly as with adsorption, so observations could also be explained without adsorption. On the other hand VL1 certainly landed onto porous regolith and frost was not observed. Hence it is suggested that adsorption is likely at both VL sites in summer.