Description: Das Projekt "Bewertung der Wirkung von Dimethylsulfid auf das Klima" wird vom Umweltbundesamt gefördert und von Universität Wuppertal, Physikalische Chemie durchgeführt. Objective/Problems to be solved: The proposed research programme is designed to resolve many of the outstanding key issues concerning the chemical transformation of DMS so that a reliable quantitative appraisal can be made of its contribution to CCN formation and consequently an assessment of the magnitude of its regulatory role in climate. Past work on the atmospheric chemistry has been instrumental in highlighting very specific processes, which need to be investigated in detail if a reliable assessment of the relationship between DMS, CCN and climate is to be made. The continuing improvement in analytical techniques now makes it possible to make high quality and high time resolution measurements of many species, both in the laboratory and in the field, which were previously either not possible or only with large error limits and poor time resolution. Scientific objectives and approach: The major objectives of the project are 1) to put constrains on the large uncertainties associated with current photochemical models by providing more accurate gas-phase kinetic and photochemical data on DMS oxidation chemistry. 2) Investigate particle formation from both DMS and DMSO. 3) Simultaneous high-time resolution measurements of dimethyl sulphide, oxidation products, halogen oxides, NO3 radical, and aerosol number/size distribution in 3 campaigns at sites with different geographical locations reflecting distinct aspects of DMS chemistry. 4) Use the data to determine the relative importance of the oxidants OH, NO3 and halogen oxides under different atmospheric conditions. 5) Use the laboratory data to construct a DMS chemistry module for CT-models capable of describing both the remote and polluted marine atmosphere and test of the models against the field data. The objectives will be achieved by a closely co-ordinated amalgamation of laboratory, field and modelling investigations. Expected impacts: The main deliverables of the project will initially be progressive constraints on kinetic/ mechanistic aspects of the oxidation chemistry of DMS and DMSO from laboratory and field experiments. This will be accompanied by high-time resolution field measurements of DMS, oxidation products, aerosols and other products relevant to the photo-chemistry. Based on this laboratory and field information a comprehensive gas/aerosol DMS-halogen-chemistry mechanism (g/a-DMS-HALO) module for incorporation in CT-models will be developed, which will be capable of describing DMS chemistry in both the remote and polluted marine atmosphere. The information can eventually be incorporated into global climatic models.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Wolkenbildung ? Wuppertal ? Messstation ? Nitrat ? Dimethylsulfid ? Meteorologie ? Halogen ? Halogenoxid ? Nitratbestimmung ? Oxid ? Oxidationsmittel ? Photochemie ? Physikalische Chemie ? Main ? Aerosol ? Luftverschmutzung ? Gasförmiger Stoff ? Chemikalien ? Daten ? Klimamodell ? Marktforschung ? Messdaten ? Modul ? Oxidation ? Standortwahl ? Witterung ? Modellierung ? Laboruntersuchung ? Fischerei ? Klima ? Forschungsprogramm ? Freilandversuch ? Atmosphäre ? Umweltschutz ? Chemische Reaktion ? Partikel ? Physikalischer Vorgang ? Atmosphärenchemie ? Auflösungsvermögen ? resources of the sea ? CT-Modell ? forecasting ?
Region: Nordrhein-Westfalen
Bounding box: 6.76339° .. 6.76339° x 51.21895° .. 51.21895°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2000-03-01 - 2003-02-28
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