HR: 0800h
AN: A51C-0591 [Abstracts]
TI: Investigation of the Influence of Microphysical Assumptions on Aerosol Chemistry Systems
AU: * Lowe, D
EM: douglas.lowe@manchester.ac.uk
AF: School of Earth, Atmospheric and Environmental Sciences,
The University of Manchester, Simon Building,
Oxford Road, Manchester, M13 9PL, United Kingdom
AU: Topping, D O
EM: david.topping@manchester.ac.uk
AF: School of Earth, Atmospheric and Environmental Sciences,
The University of Manchester, Simon Building,
Oxford Road, Manchester, M13 9PL, United Kingdom
AU: McFiggans, G
EM: g.mcfiggans@manchester.ac.uk
AF: School of Earth, Atmospheric and Environmental Sciences,
The University of Manchester, Simon Building,
Oxford Road, Manchester, M13 9PL, United Kingdom
AB:
We have developed an integrated chemical and microphysical box model, designed for examining the influence
of aerosols on halogen activation in the marine boundary layer. The chemical scheme is based on that of Pechtl
et al, pp 505-523, ACP (2006) and constructed using KPP (Sandu and Sander, pp 187-195, ACP, 2006). Non-
ideal effects on component vapour pressures for the core HNO3/H2SO4/NH3/NaCl/HCl system
are calculated using a parametrisation of the Pitzer, Simonson and Clegg mole fraction activity coefficient model.
The aerosol size distribution is represented using the sectional Moving Centre method. Currently only
condensational and evaporational particle growth is considered, coagulation is not included.
We will present the results of a study of the differences between coupled and uncoupled chemical and
microphysical aerosol representation and of the dependence of aerosol chemistry on the particle-size resolution
of the model, as well as the influence of the mixing state assumptions for sulphate and sea-salt modes has.
Such dependence critically affects the predictions of the impacts of reactive halogen cycling.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0365 Troposphere: composition and chemistry
DE: 4801 Aerosols (0305, 4906)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting