MULTI-ISOTOPE STUDY OF OZONE - IMPLICATIONS FOR THE HEAVY OZONE ANOMALY

Laboratory experiments have been performed with O and O2 in their grou nd electronic states to study the distribution of all possible ozone i sotopes formed. Results show that with respect to O-48(3) the two symm etric molecules O-17O-17O-17 and O-18O-18O-18 are depleted, in good ag reement with standard recombination theory. A large enrichment of abou t 18% is found in the asymmetric molecule O-16O-17O-18, while all othe rs carry about 2/3 of that. A comparison with past laboratory and stra tospheric ozone isotope measurements leads to the following conclusion : There is a standard enrichment which resides in asymmetric molecules only. It will lead to an enrichment of stratospheric O-49(3) and O-50 (3) of 8 to 9%; this has been actually observed in recent balloon expe riments. Occasionally, the enrichments in the stratosphere are larger, reaching 40% at certain altitudes. Only when ozone was formed in an e lectric discharge process have larger enrichments been measured in lab oratory experiments, affecting both symmetric and asymmetric molecules . The results provide an important connection between numerous laborat ory studies and stratospheric measurements.