Model simulations and aircraft measurements of vertical, seasonal and latitudinal O3 and CO distributions over Europe
1Max Planck Institute for Chemistry, Airchemistry Division, P.O. Box 3060, 55020 Mainz, Germany
2Institute for Atmospheric and Climate Science, Swiss Federal Institute of Technology, Zurich, Switzerland
3FZ Jülich, ICG-1, Jülich, Germany
Abstract. During a series of 8 measurement campaigns within the SPURT project (2001–2003), vertical profiles of CO and O3 have been obtained at subtropical, middle and high latitudes over western Europe, covering the troposphere and lowermost stratosphere up to ~14 km altitude during all seasons. The seasonal and latitudinal variation of the measured trace gas profiles are compared to simulations with the chemical transport model MATCH. In the troposphere reasonable agreement between observations and model predictions is achieved for CO and O3, in particular at subtropical and mid-latitudes, while the model overestimates (underestimates) CO (O3) in the lowermost stratosphere particularly at high latitudes, indicating too strong simulated bi-directional exchange across the tropopause. By the use of tagged tracers in the model, long-range transport of Asian air masses is identified as the dominant source of CO pollution over Europe in the free troposphere.