[1] The merged TOMS/SBUV ozone data for 1979 -2002 are used to analyze, with a linear regression model and the other approaches, the zonal distribution of ozone variations between 50°and 60°N, the seasonal cycle and trends, and the responses to the solar cycle, quasi-biennial oscillation (QBO), El Niño -Southern Oscillation (ENSO) and Arctic Oscillation (AO). The seasonal ozone cycle shows ozone high over the north Pacific and low over the north Atlantic in winter, with a variability of 180 DU between 50°and 60°N. The maximum ozone trend obtained is over À5.3 ± 0.8%/decade at around 95°E in March. The anti-phase ozone response to the equatorial QBO is about 8 DU, with a 28-month period, in zonal average. In addition, the ozone responses to ENSO and AO are detected as 5 and 8 DU, respectively, between 95°and 190°E. The zonal inhomogeneity of ozone variations between 50°and 60°N is also discussed in this study. Citation: