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

2.4. Use of a meteorological model with MODELS-3/CMAQ
In order to properly run an air quality modeling simulation, the chemistry model needs a
proper meteorological characterization of the atmosphere. With the simpler air quality models,
the meteorology was provided through a series of diagnostic analyses that typically included 12-
hourly upper-air soundings and hourly surface analyses. However, more local effects have to be
captured by air quality models. The observational network (sparse at its best), can not resolve
features of the order of 20 kilometers and several hours, particularly close to the surface. One
way to provide the required data is to use a meteorological model as a “dynamic analysis” tool.
A meteorological model can provide a dynamically consistent evolution of the atmosphere at
more frequent time intervals and higher resolutions than observations.
2.5. Compatibility of meteorological modeling with air quality modeling
Air quality modeling should be viewed as an integral part of atmospheric modeling. The
governing equations and computational algorithms should be consistent and compatible.
Previously, many atmospheric models have been built with limited atmospheric dynamics
assumptions. However, the dynamic assumptions and choice of coordinates should not precede
the computational structure of the modeling system.
The characteristics of an air quality model simulations are heavily dependent on the
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