Summary
Zonal asymmetry in quasi-stationary ozone distribution is considered in the latitude range 50-80S using satellite total ozone data. Amplitude of the quasi-stationary wave has been determined as a half-difference between maximal and minimal values in 3-month averaged ozone distribution. Besides, amplitudes of zonal harmonics have been calculated by decomposition in Fourier series. Analysis of the long-term changes has been carried out over two time periods. During first of them, in 1980s – early 1990s asymmetry in the ozone distribution was increasing due to asymmetry of developing ozone hole. After that, from mid- 1990s amplitude has been stabilized on the background of significant interannual variations. Characteristics of the spectral wave components show distinct tendencies in decadal amplitude variability of the zonal wave numbers 1 and 2, especially during 1980s and early 1990s. Dependence of wave amplitude on zonal wave number has been considered. It is shown that the amplitude is decreasing with zonal number corresponding to power law. Factor of the decrease is determined as 1.9-2.6 for quasi-stationary distribution and 0.7-1.6 for averaged daily amplitudes. So, profile of the quasi-stationary wave is mainly conditioned by wave 1.