Objetivo Problems to be solvedSTACCATO is a comprehensive study of stratosphere-troposphere exchange (STE) processes and their effect on atmospheric chemistry. STE is a key factor controlling the budget of ozone, water vapour and other substances in both the troposphere and lower stratosphere. Earlier studies of STE have concentrated primarily on the flux of air or trace constituents across the tropopause alone. Shallow exchange events are indeed partially reversible in nature and only produce compositional changes in the tropopause region. However, deep STE events are largely irreversible and have a highly significant and lasting impact on atmospheric chemistry through a substantial body of the atmosphere, even down to the earth's surface. Up until now, the importance of STE for the ozone budget relative to photochemical ozone formation from natural and anthropogenic precursor emissions, including those from aircraft, has remained uncertain. A comprehensive description of STE, which STACCATO seeks to provide, is thus a vital component for understanding the chemical composition of the atmosphere and its consequences.Scientific objectives and approachSTACCATO is undertaking a first detailed investigation of STE mixing of stratospheric and tropospheric air. Meteorological processes under investigation include the creation of fine-scale structures by chaotic advection, radiative decay of tracer filaments and mixing through turbulence in the free troposphere. The non-linear effect of this mixing on chemical processes is addressed with a box model as well as with a global model. The impact of STE on the oxidizing capacity of the troposphere, relative to other factors, is examined with two global chemistry models coupled to climate models. The fate of aircraft emissions is being addressed using passive tracer simulations and including these in the chemistry models. A new three-dimensional Lagrangian perspective of STE, focussing on deep exchange events, is being developed. The variability and recent trends of STE is being assessed, based on very high quality meteorological re-analysis data. Potential future changes to STE significance are being computed under scenarios of climate change obtained from simulations with two climate models. A major comparison of seven methods and models used to calculate STE is being carried out to find strengths and weaknesses of each approach and to identify reasons for discrepancies. A measurement dataset is being created to validate model results and to provide an independent estimate of the strength of STE. This includes the first long-term monitoring of two radio nuclides, beryllium-7 and beryllium-10.Expected ImpactsProvision of an observational estimate of the strength of STE based on two years of radio nuclide measurements. Analysis of the strength of STE and its variability during the last 15 years, based on Lagrangian models set up on meteorological re-analyses. Study of the possible changes in STE in a future climate. Assessment of the importance of STE for atmospheric chemistry relative to other factors. Improved knowledge of the role of mixing. Ámbito científico natural scienceschemical scienceselectrochemistryelectrolysisengineering and technologymechanical engineeringvehicle engineeringaerospace engineeringaircraftnatural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic changesnatural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologytroposphere Programa(s) FP5-EESD - Programme for research, technological development and demonstration on "Energy, environment and sustainable development, 1998-2002" Tema(s) 1.1.4.-2. - Key action Global Change, Climate and Biodiversity Convocatoria de propuestas Data not available Régimen de financiación CSC - Cost-sharing contracts Coordinador TECHNICAL UNIVERSITY OF MUNICH Aportación de la UE Sin datos Dirección Am hochanger 13 85 354 Freising Alemania Ver en el mapa Coste total Sin datos Participantes (10) Ordenar alfabéticamente Ordenar por aportación de la UE Ampliar todo Contraer todo ARISTOTLE UNIVERSITY OF THESSALONIKI Grecia Aportación de la UE Sin datos Dirección Aristotle university of thessaloniki 54006 Thessalonki Ver en el mapa Coste total Sin datos MAX-PLANCK-GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN E.V. Alemania Aportación de la UE Sin datos Dirección Bundesstra¯e 55 20146 Hamburg Ver en el mapa Coste total Sin datos NATIONAL TECHNICAL UNIVERSITY OF ATHENS Grecia Aportación de la UE Sin datos Dirección 9,heroon polytechniou 9 15780 Athens Ver en el mapa Coste total Sin datos ROYAL NETHERLANDS METEOROLOGICAL INSTITUTE Países Bajos Aportación de la UE Sin datos Dirección 10,wilhelminalaan 10 3730 AE De bilt Ver en el mapa Coste total Sin datos SECRETARY OF STATE FOR DEFENCE - MINISTRY OF DEFENCE Reino Unido Aportación de la UE Sin datos Dirección London road, sutton house room sg/12 RG12 2SZ Bracknell Ver en el mapa Coste total Sin datos SWISS FEDERAL INSTITUTE OF TECHNOLOGY ZUERICH Suiza Aportación de la UE Sin datos Dirección 101,hoenggerberg 8093 Zurich Ver en el mapa Coste total Sin datos UNIVERSITAET FUER BODENKULTUR WIEN Austria Aportación de la UE Sin datos Dirección 18,turkenschanzstrasse 18 1180 Wien Ver en el mapa Coste total Sin datos UNIVERSITY OF BERNE Suiza Aportación de la UE Sin datos Dirección 3,freiestrasse 3 3012 Bern Ver en el mapa Coste total Sin datos UNIVERSITY OF VIENNA Austria Aportación de la UE Sin datos Dirección Währinger strasse 17 1090 Wien Ver en el mapa Coste total Sin datos UTRECHT UNIVERSITY Países Bajos Aportación de la UE Sin datos Dirección 5,princetonplein 5 3584 CC Utrecht Ver en el mapa Coste total Sin datos