MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): an aerosol microphysical module for global atmospheric models S. E. Bauer1, D. L. Wright2,*, D. Koch1, E. R. Lewis2, R. McGraw2, L.-S. Chang2,**, S. E. Schwartz2, and R. Ruedy3 1The Earth Institute at Columbia University and NASA Goddard Institute for Space Studies, New York, USA 2Brookhaven National Laboratory, Upton, New York, USA 3Sigma Space Partners (SSP) and NASA Goddard Institute for Space Studies, New York, USA *present address: School of Arts and Sciences, Rutgers University, New Brunswick, NJ 08901, USA **present address: Global Res. Center, National Institute of Environmental Res., Kyungseo-dong Seo-gu, Incheon, Korea
Abstract. A new aerosol microphysical module MATRIX, the Multiconfiguration
Aerosol TRacker of mIXing state, and its application in the Goddard Institute
for Space Studies (GISS) climate model (ModelE) are described. This module,
which is based on the quadrature method of moments (QMOM), represents
nucleation, condensation, coagulation, internal and external mixing, and
cloud-drop activation and provides aerosol particle mass and number
concentration and particle size information for up to 16 mixed-mode aerosol
populations. Internal and external mixing among aerosol components sulfate,
nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are
represented. The solubility of each aerosol population, which is explicitly
calculated based on its soluble and insoluble components, enables calculation
of the dependence of cloud drop activation on the microphysical
characterization of multiple soluble aerosol populations.
A detailed model description and results of box-model simulations of various
aerosol population configurations are presented. The box model experiments
demonstrate the dependence of cloud activating aerosol number concentration
on the aerosol population configuration; comparisons to sectional models are
quite favorable. MATRIX is incorporated into the GISS climate model and
simulations are carried out primarily to assess its performance/efficiency
for global-scale atmospheric model application. Simulation results were
compared with aircraft and station measurements of aerosol mass and number
concentration and particle size to assess the ability of the new method to
yield data suitable for such comparison.
The model accurately captures the observed size distributions in the Aitken
and accumulation modes up to particle diameter 1 μm, in which sulfate,
nitrate, black and organic carbon are predominantly located; however the
model underestimates coarse-mode number concentration and size, especially in
the marine environment. This is more likely due to oversimplifications of the
representation of sea salt emissions – sea salt emissions are only calculated
for two size classes – than to inherent limitations of MATRIX.
Citation: Bauer, S. E., Wright, D. L., Koch, D., Lewis, E. R., McGraw, R., Chang, L.-S., Schwartz, S. E., and Ruedy, R.: MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): an aerosol microphysical module for global atmospheric models, Atmos. Chem. Phys., 8, 6003-6035, doi:10.5194/acp-8-6003-2008, 2008.