MLS CLO OBSERVATIONS AND ARCTIC POLAR VORTEX TEMPERATURES

Analysis of UARS MLS observations in early January 1992 shows a clear relationship between predicted polar stratospheric cloud formation alo ng the back trajectory and elevated ClO amounts. These findings are in good agreement with aircraft observations. The MLS observed variation of ClO amounts within the vortex also fits the pattern of ClO change as a result of air parcel solar exposure and nitric acid photolysis. O utside the polar vortex, the occasional highly elevated ClO appear sta tistically consistent with MLS measurement noise.