HR: 17:00h
AN: A14C-04    [Abstracts]
TI: COUPLING AEROSOL AND CLOUD MICROPHYSICS WITH MULTIPHASE CHEMISTRY
AU: * LERICHE, M
EM: M.Leriche@opgc.univ-bpclermont.fr
AF: LAMP CNRS, UNIVERSITE BLAISE PASCAL 24 AVENUE DES LANDAIS, AUBIERE, 63177 France
AU: CHAUMERLIAC, N
EM: N.Chaumerliac@opgc.univ-bpclermont.fr
AF: LAMP CNRS, UNIVERSITE BLAISE PASCAL 24 AVENUE DES LANDAIS, AUBIERE, 63177 France
AU: DEGUILLAUME, L
EM: L.Deguillaume@opgc.univ-bpclermont.fr
AF: LAMP CNRS, UNIVERSITE BLAISE PASCAL 24 AVENUE DES LANDAIS, AUBIERE, 63177 France
AB: A multiphase chemistry model coupled with a quasi-spectral microphysical model, including aerosol particle activation has been applied to measurements from the European CIME campaign to quantify the formation of the strong acids nitrate and sulfate, and to evaluate the role of microphysical processes in redistributing reactive species among the different phases (gas, aerosols particles versus cloud and/or rain). Significant formation of nitrate and sulfate are found to be due to the reaction of pernitric acid with the sulfite ion. Moreover, pernitric acid, because of its equilibrium in the gas phase and its high solubility, is always available both in cloud water and in rainwater via mass transfer from the gas phase. The sulfite ion comes from the mass transfer from the gas phase of sulfur dioxide in cloud water. When rain formation begins, it is efficiently transferred to the rainwater by collision/coalescence processes. This leads to an enhancement in strong acid production when microphysics is activated in the model. Modeled results have been compared with experimental data, in an effort to retrieve a behavior law related to the partitioning between the gas and aqueous phases of the cloud. In particular, when collision/coalescence processes are considered, an improvement in retrieving the partitioning of soluble species and especially nitrate is observed. Also, model results provide an indication for the relative contributions of gas versus particle phases to sulfate and nitrate concentrations in clouds.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0320 Cloud physics and chemistry
DE: 0345 Pollution--urban and regional (0305)
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting