Assessing ozone loss over Europe - Commission launches THESEO campaign
The European Commission has just launched the Third European Stratospheric Experiment on Ozone (THESEO) - an ambitious coordinated campaign to monitor and study ozone loss over Europe. Following on from two earlier European campaigns - EASOE and SESAME - which contributed to a better understanding of ozone loss in the Arctic stratosphere, THESEO will focus on ozone loss processes over Europe. The Commission's support to research on stratospheric ozone and UV-B radiation, for which some ECU 16 million has already been ear-marked, reflects the growing concern over the huge ozone depletion that has occurred in the Arctic stratosphere during each of the last three winters, and the long-term ozone decline over Europe. The overall aim of the THESEO campaign is to improve understanding of the processes underlying the observed mid-latitude trends. This is an ambitious goal as the processes occurring over mid-latitudes are more complex and subtle than in the Arctic vortex, and any perturbations to the amount of ozone will be smaller than in the polar vortices. It is known that chlorine and bromine compounds are responsible for most ozone loss over Europe, but the relative contributions of various other processes are not well understood - e.g. the effects of aircraft emissions and links with climate change. The main emphasis in THESEO is to study ozone loss over populated areas, as well as connections with Arctic ozone loss. The THESEO campaign consists of a core of 12 major projects funded by the EU within the framework of the specific RTD programme in the field of Environment and Climate, each with its own focused goals. This research work is closely coordinated with, and substantially increased by, national research programmes. The campaign, which will run until the end of 1999, will involve over 400 scientists in the EU, as well as participation from Canada, Iceland, Japan, Norway, Poland, Russia, South Africa, Switzerland and the United States.