Objective To increase our understanding of ozone's role as a greenhousegas.The project will focus on identifying and understanding thechanges in the ozone content of the upper troposphere and thelower stratosphere, and both the causes and the effects of thesechanges will be studied with a wide range of atmospheric models.Emphasis will be put on identifying possible regional differencesin the trends and in the climate response to the changedradiative forcing, rather than on globally averaged quantities.The workplan is divided into four subtasks: data analysis,chemical modelling, radiative transfer modelling, andclimate modelling.In the data analysis part both ozone sonde observations andsatellite measurements of total ozone will be analyzed in orderto get a coherent picture of the current and past trends in theozone distribution. Specifically we will try to determine howwidespread the ozone loss that is observed in the lowerstratosphere is, as well as where exactly the crossover betweenthis stratospheric ozone loss and the corresponding troposphericincrease occurs.Two- and three-dimensional chemical models will be used as toolsboth for understanding what determines the observed trends, andfor predicting future trends in the ozone distribution. A keyissue for the chemical modelling is to determine the extent towhich the lower stratospheric ozone reductions seen over the lastdecade can be attributed to increased emissions of CFCs andhalons. In addition the impact on upper troposheric ozone ofNOx emissions from commercial flights will be studied.The impact of various observed and modeled profiles of ozone onthe atmospheric heating rates will be studied using radiativetransfer models. This work will be particularly useful forputting the ozone/climate issue into the proper perspective, asit will quantify how important the latitudinal (or regional)changes in radiative forcing can be, compared to the radiativeforcing from other greenhouse gases.Finally the atmospheric response to changes in heating ratesthrough a redistribution of ozone will be studied using climatemodels. This work will help in identifying possible positive ornegative feed-back mechanisms relevant for the ozone/climatequestion, and simulations with ozone as a predicted variable in ageneral circulation model may also give some ideas about how theatmsphere would redistribute the ozone in response to externallyenforced ozone reductions. Fields of science natural sciencescomputer and information sciencesdata scienceengineering and technologymechanical engineeringvehicle engineeringaerospace engineeringsatellite technologynatural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologytroposphere Programme(s) FP3-ENV 1C - Specific research and technological development programme (EEC) in the field of the environment, 1990-1994 Topic(s) 0102 - Anthropogenic climate change Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator DANISH METEOROLOGICAL INSTITUTE Address 100,lyngbyvej 100 2100 Koepenhagen Denmark See on map EU contribution € 0,00 Participants (5) Sort alphabetically Sort by EU Contribution Expand all Collapse all ARISTOTLE UNIVERSITY OF THESSALONIKI Greece EU contribution € 0,00 Address Aristotle university of thessaloniki 54006 Thessalonki See on map Institut Pierre Simon Laplace des Sciences de l'Environnement Global France EU contribution € 0,00 Address 4 place jussieu 75252 Paris See on map UNIVERSITY OF READING United Kingdom EU contribution € 0,00 Address Earley gate 2, whiteknights, palmer building RG6 2AU Reading / silchester See on map University of Oslo Norway EU contribution € 0,00 Address 0315 Oslo-blindern See on map Università degli Studi dell'Aquila Italy EU contribution € 0,00 Address Via vetoio 10 67010 Coppito l'aquila See on map