Goldschmidt2013 Conference Abstracts

1202

A study of combustion aerosols inJapan using a nonhydrostatic
icosahedral atmospheric model

D. GOTO *, K. SUZUKI AND SALSA PROJECT TEAM
1

2

Thermodynamics of solid solutions:
the Margules equation and beyond
M. GOTTSCHALK*

3National Institute for Environmental Studies, Ibaraki 3058506, Japan (*correspondence: goto.daisuke@nies.go.jp)
2
JPL/CalTech, California (Kentaro.Suzuki@jpl.nasa.gov)
3
REsearch program on Climate Change Adaptation (RECCA)/ development of Seamless chemical AssimiLation Systemand its Application for atmospheric environmentalmaterials (SALSA project), Japan1

An aerosol-coupled global cloud-resolving model,
NICAM-SPRINTARS, developed by [1] based on the aerosol
module of Spectral Radiation-Transport Model for Aerosol
Species (SPRINTARS; [2]) and the global cloud-resolving
model of Nonhydrostatic Icosahedral Atmospheric Model(NICAM; [3,4]) is capable to simulate the aerosol processes
and distributions not only in the whole globe but also over
specific regions using a stretched grid system developed by [5]as a ‘seamless’ model. In the present study, we develop theseamless aerosol-transport model with the spatial resolution of
about 10 km to simulate aerosols around Japan, especially theKanto region including Megacity Tokyo.
Although in some cities near mountains the present model
does not always reproduce both the meteorological andaerosol fields mainly due to large spatial resolution, aroundthe center of Tokyo it can sucessfully simulate meteorologicaland aerosol fields such as sulfate (Figure). In the presentation,
we will discuss the performance of the newly developed
aerosol model.

GeoForschungsZentrum Potsdam, 14473 Potsdam, Germany,(*correspondence: gottschalk@gfz-potsdam.de)
For the thermodynamic treatment of phase equilibria theknowledge of Gibbs free energy G of solid solutions areessential. The thermodynamic models used for solid solutions
are mostly the regular solution, the Margules-, and the
Guggenheim-equation. The calibration of the involved
parameters involves the results from phase equilibria studies.
Alternatively, the lattice energy is calculated on the atomistic
scale by using empirical force potentials or ab-initio
calculations. Cluster expansion and applying statisticalmechanics e.g. Monte Carlo methods are then used to evaluate
G. For thermodynamic calculations parameterization of theGibbs free energy rely then on the same models as for thethermodynamic approach.
The regular solutions and the Margules equation originate
from fluid mixtures. A general approach can be applied tosolids considering, that the molar mixing energy u depends on
xi and the occupancy xj of neighboring adjacent or more distantsites. For one neighbor of the same site, u is:which gives us the regular solution:
If the energy depends on two neighboring sites
results in the Margules equation including a ternary term:

The above equation can also be written in theform:
Figure 1: Simulated sulfate around Japan in unit of µg/m3.
[1] Suzuki et al. (2008) Geophys. Res. Lett. 35, L19817,
doi:10.1029/2008GL035449. [2] Takemura et al. (2005) J.
Geophys. Res. 110, D02202, doi:10.1029/2004JD005029. [3]Tomita and Satoh (2004). Fluid Dyn. Res., 131, 1033-1050.
[4] Satoh et al. (2008). J. Comput. Phys. 227, 3486-3514. [5]Tomita (2008) J. Meteor. Sco. Japan, 86A, 121-142.

This procedure can be extended to more complex interactions.
If the energy of the site depends on the occupancy of four ofthe same site and two of a neighboring site:
It is important to note that these types of equations always
split in a term for the mechanical mixture and one involving
only parameters !U based on energy differences, which canbe acquired by theoretical calculations for complex andarbitrary system.

www.minersoc.org
DOI:10.1180/minmag.2013.077.5.7