Alternative small scale meteorology input to a chemical transport ...

quality of meteorological data. Meteorological data for air quality models can be provided either
by diagnostic models, which analyze observations at surface meteorological sites and upper air
soundings, or by dynamic meteorological models. Development of a fully coupled chemistry
transport model to a meteorological modeling system should satisfy the following requirements
(Byun et al, 1999):
(i) Scalable dynamics and thermodynamics: Use of fully compressible form of governing
equations and flexible coordinate system that can deal with multiscale dynamics;
(ii) Unified governing set of equations: Not only the weather forecasting, dynamics and
thermodynamics research, but also the air quality studies should rely on the same
general governing set of equations describing the atmosphere;
(iii) Cell based mass conservation: As opposed to the simple conservation of domain
total mass, cell based conservation of the scalar (conserving) quantities is needed. Use
of proper thermodynamic variables, such as density instead of pressure and
temperature, and representation of governing equations in the conservation form rather
than in the advective form are recommended;
(iv) State-of-the-art data assimilation method: Not only the surface measurements and
upper air soundings, but also other observation data obtained through remote sensing
and other in situ means must be included for the data assimilation;
(v) Multi-scale physics descriptions: It has been known that certain parameterizations of
physical processes, including clouds, used in present weather forecasting models are
scale dependent. General parameterization schemes capable of dealing with a wide
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