Satellite observed long-term averaged seasonal and spatial ozone variations in the stratosphere

Nine years of Nimbus-7 SBUV ozone mixing ratio data (October 1978–September 1987) have been used to analyze the distributions of the long-term average annual and semiannual ozone oscillations in the lower, middle, and upper stratosphere over the region 65°S to 65°N. It is shown that the derived harmonics are consistent with the results of earlier investigations based on limited sets of data. Year-to-year changes of amplitudes of the annual and semiannual variations are generally small except in the tropical midstratosphere (due to the effect of El Chichon) and the southern subpolar upper stratosphere.

Analyses are also presented to show the vertical and seasonal distribution of the zonal ozone variations. It is shown that, for the long-term averaged data, wave 1 is larger during winter than summer and in winter larger in the Northern than Southern Hemisphere. The importance of photochemical and thermal/dynamic processes in modifying the time and zonal variations is discussed.