A reanalysis of carbonyl sulfide as a source of stratospheric background sulfur aerosol

Abstract

This study investigates the importance of carbonyl sulfide (OCS) in the formation of stratospheric background sulfur aerosol. Specific questions examined include the loss rate in the stratosphere, the net flux into the stratosphere, and the contribution of OCS to the stratospheric background sulfur aerosol. The global atmospheric lifetime of OCS is estimated to be 4.3 years. Using a one-dimensional photochemical model, the stratospheric photochemical lifetime of OCS is estimated to be 10 years, more than 2 times longer than its global atmospheric lifetime. These results suggest that most of the OCS transported into the stratosphere returns to the troposphere where it is mainly taken up by surface vegetation. -from Authors