• Introduction
• Long term ozone trends
  • Total ozone trends
  • Season-height trends
• Instrumental research

Season-height trends

Information on the vertical distribution of ozone is obtained from ozone soundings. The vertical profile time series have been homogenised and are now of the highest possible quality for further research.

At RMIB, several projects are running, using this homogenised data. Ozone trend studies are very important to learn more about the atmospheric behaviour of ozone. The trends in the figure below are the result of a least square linear regression on the monthly mean ozone partial pressures. For more than 30 years of measuring, the general trends are increasing in the troposphere and decreasing in the stratosphere.

Season-height cross-section of ozone trends in percent per year at Uccle for the period January 1969 to December 2003. Areas where the trend is statistically significant at the 95 % level are coloured darker (red for negative and blue for positive trends).