The paper deals with the modeling of the evolution (chemical kinetics) of tropospheric small ions for the case where the rate of ion generation is substantially above normal. Such types of situations can be found in the regions where because of either natural or artifical conditions the rate of ion generation is increased. This model would be applicable to the results of the measurements performed a few years ago in Chernobyl and also to the lab instruments, where enhanced ionization is used. This paper deals only with the effects which are caused by the evolution of negative ions. The concentrations of positive ions have been calculated for the natural concentrations of neutral gases and henceforth are considered constant. The model considers only ion-molecular reactions; the reactions between neutral compounds have not been taken into account.

The model describing the kinetics of positive ions contains 1048 reactions, 199 ions, and 131 neutral compounds; the negative ion model includes 474 reactions, 143 ions, and 106 neutral compounds. The results show that if the ionization rate is substantially increased, the concentrations of neutral gases will change. Many of these changes can be estimated. The estimated concentrations are (in cubic centimeters): =2.0¿1010; 2>= 3.5¿107; 2O>=8.0¿1013; 3>=1.0¿107; 2>=3.0¿108. Next, the concentrations of OH, O, N, H, HNO2, HO2, and CH3 increase nearly independently of the concentrations of neutral gases. The extent of the change in the concentrations of OH, O, N, HNO2, HO2, and CH3 cannot be estimated, as the feedback processes through ion-molecular reactions are practically absent. The chemical kinetics of ions at a given gas composition is significantly different from the kinetics at the normal gas concentrations, i.e., because of both the changed concentrations of neutral gases and the shortened lifetimes of ions. In the steady state the ions O2- (H2O)k become dominant, whereas the ions CO3-(H2O)k hold the second place. ¿ American Geophysical Union 1994