STRATOSPHERIC OZONE RESPONSE TO SHORT-TERM AND INTERMEDIATE-TERM VARIATIONS OF SOLAR UV FLUX

On the basis of three years (October 1991 through September 1994) of U ARS SOLSTICE (solar stellar irradiance comparison experiments) and MLS (microwave limb sounder) data, correlations between tropical ozone an d spectral solar UV flux have been studied. In addition to the 27-day period of solar rotation, this new result shows a relatively weak UV-o zone correlation at periods of 60-80 days in the upper stratosphere. T he 60-80 day correlation coefficient (similar to 0.5) is somewhat smal ler than the 27-day correlation (similar to 0.7). For the 60-80 day pe riodicity the overall phase lag of ozone is about 2 weeks throughout t he 1-10 mbar layer, but the phase relation differs each year. This sug gests that dynamical effects could be influencing the 60-80 day ozone variation. Although the 60-80 day solar variation is much smaller than the 27-day variation, the ozone response to these solar variations is about as strong. Further investigation of the 60-80 day variation usi ng alternate data sets for different time periods would be desirable.