Lifetime of Odd Oxygen

Abstract

Data on the lifetime of odd oxygen Ox in the Northern Hemisphere at a latitude range of 10°–80° in December and June 1995 are presented. These data were obtained using the SOCRATES interactive two-dimensional radiation-chemical model, in which the total destruction rate of Ox in the catalytic cycles of Ox, HOx, NOx, ClOx, and BrOx and the concentration of Ox, equivalent to a sum of O3, O(3P), and O(1D) concentrations for the above conditions, all of which it is necessary to know to calculate the lifetime of Ox, were previously calculated. The RCP 4.5 scenario of the Intergovernmental Panel on Climate Change (IPCC) for the conditions of December and June 1995 was used as the initial conditions for calculations using the SOCRATES model. It is shown that in June, the atmospheric lifetime of Ox lie in a rather narrow altitudinal–latitudinal interval, and the lifetimes for December and June in the lower stratosphere are the same, which is explained by the same conditions in this zone during these seasons. It is also shown that at higher altitudes and latitudes, the lifetimes of odd oxygen in December are significantly longer than those in June, which largely explains the difference in the destruction rates of odd oxygen in December and June.