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

major modeling systems from this period were the Sulfur Transport and Emissions Model
(STEM) (Carmichael and Peters, 1984a, 1984b), the Regional Acid Deposition Model
(RADM) (Chang et al., 1987), the Acid Deposition and Oxidant Model (ADOM) (Venkatram
et al., 1988), the Urban Airshed Model (UAM) (Morris and Meyers, 1990). These models
were designed to address specific air pollution issues such as ozone or acid deposition and to
be applied under relatively prescriptive implementation guidance strategies. Thus, flexibility to
deal with other issues, such as particulate matter or toxics, was very limited.
Additional air pollution issues were identified, including visibility, fine and coarse
particles, semi-volatile organic species, and nutrient deposition to water bodies. The direct
response approach was to modify, adapt or extend current models to handle more complex
implementations. This approach was both cumbersome and limiting. Seeking a more strategic
approach to handle the increased modeling requirements, more comprehensive modeling
approaches were needed. With increasing computer capabilities, the opportunity arose for
design of a system that would both meet and keep pace with the increasing requirements on air
quality modeling and incorporating advances in state-of-science descriptions of the atmospheric
processes.
To simulate the air quality and weather phenomena realistically, adaptation of the “one
atmosphere” perspective is necessary. This perspective is based on “first principles” description
of the atmosphere and emphasizes that the influence of interactions at different dynamic scales
and among multi-pollutants cannot be ignored. For example, descriptions of processes critical to
producing oxidants, acid and nutrient depositions, and fine particles are too closely related to
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