OZONE DEPLETION IN THE ARCTIC STRATOSPHERE IN EARLY 1993

During the first three months of 1993 measurements of the vertical ozo ne profile, with balloon-borne sensors, were performed in Greenland. A substantial ozone depletion took place from the end of January to the end of March in the altitude range between approximately 14 and 20 km . An ozone decrease of about 1% per day is ascribed to chemical destru ction inside the polar vortex based on air parcel trajectory analysis, using measurements of lower stratospheric aerosols as dynamical trace rs to correct for diabatic subsidence. The column-integrated total ozo ne loss was found to be about 48 Dobson units or 12%. These measuremen ts are in good agreement with satellite observations, and further docu ment the 1993 springtime stratospheric ozone depletion as the most sev ere and long lasting yet reported for the Arctic.