Mechanisms of the stratospheric ozone depletion: II. Chain length and the rate of ozone depletion in the main stratospheric cycles

Abstract

A detailed analysis of chain mechanisms of stratospheric ozone destruction in the Ox, HOx, NOx, ClOx, and BrOx cycles is performed and an algorithm for calculating the characteristics of the limiting stages of chain propagation and chain terminations and the chain length for these cycles is proposed. It is shown that a proper description of ozone destruction in these chain processes is only possible through the determination of the rates of limiting steps, while the simple addition of the rates of the reactions in which odd oxygen is lost leads to a significant overestimation of the calculation results. The role of the zero chain processes in these cycles. It is shown that these processes play a decisive role in the formation of the families of odd oxygen, nitrogen, chlorine, and bromine. Based on the methods developed and the results of calculations within the framework of the Socrates two-dimensional model, the rate of ozone loss and the length of the chain in these cycles for the model conditions of June 2000 at a latitude of 65° N are determined. The results make it possible to compare the effectiveness of ozone cycles and more fully assess their contribution to the destruction of the ozone layer, both in the past and in the future.