Objective Theoretical studies have indicated that, especially during summer, two-way exchange across the midlatitude tropopause can occur relatively freely. This is supported by a limited number of aircraft measurements (e.g. by this group), indicating that polluted tropospheric air can be mixed into the lowermost stratosphere. This can have important implications for ozone trends and aircraft emissions in this part of the atmosphere. The first objective of the proposed project is to investigate the effects of stratosphere-troposphere exchanges on the chemical composition of the lowemmost stratosphere in northem mid-latitudes. Particular emphasis is given to the budget of reactive nitrogen species (NOy). The research will be performed on the basis of aircraft measurements over Canada, the North-Atlantic Ocean and westem Europe, during the summer of 1998. The measurements will provide a basis for modelling studies. The project involves deployment of a high flying twinjet aircraft (70 flight hours) to measure nitrogen oxides, ozone, water vapor, aerosols, sulphur species, carbon monoxide, hydrocarbons and many other gases to quantify the chemistry and dynarnical history of air parcels in the lowemmost stratosphere. These studies will be supported by high resolution ECMWF meteorological analyses, back-trajectory calculations and associated chemistry modelling. The measurements will guide 3-D chemistry-transport and radiative transfer simulations to simulate the consequences of anthropogenic perturbations. In particular, we will assess the importance of cross-tropopause exchanges of trace species relative to aircraft emissions in the lowemmost stratosphere. In addition to these pollution studies we plan to investigate the sulphur budget of the unperturbed lower stratosphere. This will be particularly interesting if no major volcanic eruptions reach the stratosphere before our campaign in the summer of 1998. The measurements will quantify the relationship between carbonyl sulphide and sulphate and provide a much needed basis for model calculations of the stratospheric sulphur cycle. The project will reinforce the collaborative efforts of 9 European research groups and a Canadian group that have collaborated successfully in the past. This proposal requests support for a 2 year project that includes a 40 flight hour measurement campaign, and the salaries of 1.5 technical staff, 8 Ph.D students and post-docs to prepare and participate in the measurements, data analysis and their interpretation. The Canadian part of the campaign (30 flight hours) and scientific contributions by York University, will be supported through Canadian resources. Fields of science natural sciencescomputer and information sciencesdata sciencenatural scienceschemical sciencesinorganic chemistryinorganic compoundsengineering and technologymechanical engineeringvehicle engineeringaerospace engineeringaircraftnatural scienceschemical sciencesorganic chemistryhydrocarbonsnatural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologytroposphere Programme(s) FP4-ENV 2C - Specific programme of research and technological development in the field of environment and climate, 1994-1998 Topic(s) 01020101 - Stratospheric chemistry and depletion of the ozone layer Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator UTRECHT UNIVERSITY EU contribution No data Address 5,Princetonplein 5 3584 CC UTRECHT Netherlands See on map Total cost No data Participants (9) Sort alphabetically Sort by EU Contribution Expand all Collapse all DELFT UNIVERSITY OF TECHNOLOGY Netherlands EU contribution No data Address 1,Kluyverweg 1 2600 GB DELFT See on map Total cost No data Forschungszentrum Jülich GmbH Germany EU contribution No data Address 52425 Jülich See on map Total cost No data JOHANN WOLFGANG GOETHE UNIVERSITAET FRANKFURT Germany EU contribution No data Address Georg-Voigt-Strasse 14 60325 FRANKFURT AM-MAIN See on map Total cost No data Koninklijk Nederlands Meteorologisch Instituut Netherlands EU contribution No data Address 3730 AE De Bilt See on map Total cost No data MAX-PLANCK-GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN E.V. Germany EU contribution No data Address 55020 MAINZ See on map Total cost No data MAX-PLANCK-GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN E.V. Germany EU contribution No data Address Saarstraße 23 55020 MAINZ See on map Total cost No data MAX-PLANCK-GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN E.V. Germany EU contribution No data Address Saupfeicheckweg 1 69117 HEIDELBERG See on map Total cost No data STOCKHOLM UNIVERSITET Sweden EU contribution No data Address 12,Svante Arrheniusväg 12, Arrhenius Laboratory 106 91 STOCKHOLM See on map Total cost No data The Canadian Institute for Research in Atmospheric Chemistry Canada EU contribution No data Address 4700,Keele Street M3J 1P3 North York See on map Total cost No data
