Atomic Chlorine and the Chlorine Monoxide Radical in the Stratosphere: Three in situ Observations

Science  04 Nov 1977:
Vol. 198, Issue 4316, pp. 501-503
DOI: 10.1126/science.198.4316.501


Three simultaneous observations of atomic chlorine (Cl) and the chlorine monoxide radical (ClO) are reported which encompass the altitude interval between 25 and 45 kilometers. Together, Cl and ClO form a gas-phase catalytic cycle potentially capable of depleting stratospheric ozone. Observed Cl and C1O densities, although variable, imply that chlorine compounds constitute an important part of the stratospheric ozone budget. The results are compared with recent models of stratospheric photochemistry which have been used as a basis for predicting ozone depletion resulting from fluorocarbon release.