Description: Das Projekt "Modelling of aerosol effects in mixed-phase clouds" wird vom Umweltbundesamt gefördert und von Paul Scherrer Institut, Labor für Atmosphärenchemie durchgeführt. As summarised in the 4th IPCC report, the indirect effect of aerosols on cloud properties constitutes the single largest remaining uncertainty in the climate system. In this project, we propose to make use of a uniquely comprehensive set of observations, in combination with detailed microphysical modelling, to develop accurate ice nucleation parameterisations for different types of aerosol in mixed-phase clouds. Further, we will use the combination of a detailed microphysical box model and a highly resolved three-dimensional model (the weather research and forecasting model, WRF) with spectral bin microphysics, to determine which dynamical processes need to be accounted for, in order to accurately represent the cloud microphysical properties. One of our main objectives in this work, which makes this project novel and original, is to contribute to the resolution of the recent controversy surrounding the efficiency of black carbon aerosol as an ice nucleus. The development of model parameterisations of ice nucleation in clouds is often hampered by the necessity to base the parameterisations on idealised laboratory experiments, and by the paucity of cloud microphysical measurements suitable for model validation. However, this project is in a unique position to benefit from several observational data sets gathered during recent measurement campaigns. The observations on which we will base the modelling work are performed at the high altitude Swiss research station on the Jungfraujoch and provide a highly detailed description of the physical and chemical properties of the ice nucleating aerosol particles in ambient clouds. In addition, they describe the microphysical properties of the observed clouds. The measured aerosol properties give us the benefit of being able to initialise the models with the actual aerosol found in the clouds, rather than an idealised background aerosol derived from emission inventories or large scale models. The observed cloud microphysical properties will allow us to constrain and validate the model simulations in exceptional detail. The models will be tested in their original form, with their existing microphysical parameterisations, and these will then be further developed until the models can represent the observed cloud properties. Special attention will be given to the roles of black carbon (BC) aerosol, because of its anthropogenic source, and the uncertainty surrounding its activity as an ice nucleus (IN) and to mineral dust, because of its high IN activity. We will further use the combination of models and observations to try to identify other important IN components in the observed aerosol, such as biogenic particles or organic species. (...)
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Wolkenbildung ? Wolke ? Bewölkung ? Gesteinsstaub ? Weiterverwendung ? Mineralstaub ? Buchhaltung ? Zellkern ? Main ? Schweiz ? Emissionsinventar ? Black Carbon ? Aerosol ? Topographie ? Verfahrenskombination ? Wirkung ? Strahlung ? Gelöster organischer Kohlenstoff ? Prognosemodell ? Simulationsmodell ? Wirkungsgrad ? Laborversuch ? Verwitterung ? Modellierung ? Chemische Stoffeigenschaft ? Wirkung ? Messung ? Atmosphärenchemie ? Klimasystem ? Anthropogener Einfluss ? Arbeit ? Bedarf ? Forschung ? Forschungseinrichtung ? Klima ? Partikel ? Wetter ? DATENSATZ ? WICHTIG ? BESTEHEND ? BESONDER ? aerosol-cloud interaction ? BETRACHTUNG ? climate forcing ? Art [Spezies] ? BEWERTEN ? Basen [chemisch] ? Buchgrundstück ? BESCHREIBUNG ? mixed-phase clouds ? EIN ? EINSATZ ? ENTWICKLUNG ? ERFORDERNIS ? EXPERIMENT ? Erlass [Recht] ? FORMBLAETTER ? Haltestelle ? MISCHUNG ? Muskelarbeit ? NEU ? Ortsbestimmung ? PROJEKT ? RATIFIKATION ? SONSTIG ? STELLE ? UMLAND ? BESTANDTEIL ? VORSCHLAGEN ? VORTEIL ?
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2013-01-01 - 2015-06-30
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