Box model studies of ClO[sub x] deactivation and ozone loss during the 1991/92 northern hemisphere winter

The authors present the results of a box type photochemical model applied to study the evolution of chlorine oxides in the arctic stratosphere. Earlier studies have shown that during the January 1992 time frame, cold temperatures, and the presence of polar stratospheric clouds mediated the formation of excess quantities of chlorine oxides in the stratosphere. In practice these active gasses did not significantly impact ozone because of the lack of sunlight to drive photochemical reactions. As temperature warmed, this excess active chlorine level relaxed back to more stable reservoir molecules such as ClONO[sub 2]. The authors use their model to study the time evolution of this change, and the impact volcanic aerosols had on the rates.