Statistical Study on the Lower Mesospheric and Upper Stratospheric Ozone Changes Observed by Aura MLS Satellite During the Multiple Solar Eclipses

Abstract Solar eclipse events (SEs) provide an excellent natural experiment for the response of the middle atmosphere to short‐term changes in solar radiation. For this study, we quantify radiation variations through obscuration, which is defined as the fraction of the solar disk obscured by the Moon during SEs. Using Aura Microwave Limb Sounder satellite observations, we analyze the changes in the average ozone mixing ratio at the upper stratosphere and the lower mesosphere during multiple SEs since July 2004. The results show that during SEs, ozone at the upper stratosphere and the lower mesosphere is sensitive to short‐term solar radiation changes and increases to about twice the normal daytime ozone mixing ratio. The ozone increase tends to level off with increasing obscuration during SEs, especially near the totality. We estimate that the effect of water vapor photolysis, the primary photochemical process of mesospheric ozone depletion, is greatly suppressed during SEs. Furthermore, we detect O 3 changes at 0.46 hPa, which cannot be explained solely by changes in temperature or solar radiation. However, CO observation, a long‐lived tracer, did not reveal any common characteristics in dynamical behavior related to O 3 changes near the stratopause.