Ozone, UV and Aerosol studies

STCEO3 (Solar Terrestrial Centre of Excellence for ozone and UV)

Roeland Van Malderen, Quentin Laffineur, Veerle De Bock, Hugo De Backer
Royal Meteorological Institute
Ringlaan 3,
B-1180 Brussels, Belgium

Contact: Roeland Van Malderen (ozone, water vapour), Veerle De Bock (UV, aerosols) or Quentin Laffineur (LIDAR)


The Solar Terrestrial Centre of Excellence co-ordinates activities of the three institutes (KMI-IRM, BIRA-IASB, KSB-ORB) of the spacepole at the plateau of Uccle. The main purpose is to support long term activities. The Ozone Aerosol UV group is contributing to this centre with the long term monitoring of the ozone layer with the spectrophotometers and the ozone soundings. Also the prediction and the measurement of the UV radiation is part of the project.


The time series of vertical ozone profiles, total ozone column densities, and UV spectral irradiation measurements data will be exploited to study

  • the ozone budget over mid-latitudes,
  • tropospheric ozone events,
  • the interactions between changes in aerosol and ozone content of the atmosphere and climate changes,
  • the effect of aerosols on the UV radiation reaching the ground,
  • the effect of the aerosol properties on the accuracy of broadband UV observations.

Within the STCE, a collaboration between the three Space Pole institutes has been started in the field "Water Vapour, Meteorology, and Climate". The aim of this project is to bring together the expertises of the institutes in order to make progress in the weather forecast, nowcasting and climate research by incorporating more water vapour data or model output. An overview of the ongoing actions and opportunities can be found here.

Our group focuses on Integrated Water Vapour (IWV) observations for climate change analysis:

  • first, we undertake a world-wide intercomparison study of IWV measurements by five different techniques: 2 ground-based instruments (GPS and CIMEL sun photometer), 1 in-situ instrument (radiosondes), and 2 satellite devices (in the UV/VIS, GOME/SCIAMACHY/GOME-2, and in the IR: AIRS). A special emphasis in this study is on the impact of cloud cover on and the geographical dependency of the techniques intercomparison.  The ultimate goal of this first part is to assess which instruments and datasets can be used for IWV trends analyses.
  • next, we do a time series analysis of the homogeneous and consistent IWV datasets. Issues that are specifically dealt with in this part are day-night trend differences, the impact of observational biases (cloud cover) on trends and the geographical consistency of the IWV trends.