Research Projects

Project at a Glance

Project Status: complete

Title: Design for a non-steady-state air quality modeling system

Principal Investigator / Author(s): Scire, Joseph S

Contractor: Sigma Research Corporation

Contract Number: A5-194-74

Research Program Area: Atmospheric Processes

Topic Areas: Modeling


Sigma Research Corporation has been awarded a contract by the California Air Resources Board (ARB) to design and develop a generalized non-steady-state air quality modeling system for the State of California. Systems Application, Incorporated (SAI) is a subcontractor to Sigma Research and has the responsibility of developing the wind field-modeling component of the modeling system.

The ARB design specification for the model include: 1) point and area source capabilities, 2) a modeling domain from tens of meters to hundreds of kilometers from the source, 3) predictions for averaging times ranging from one hour to one year, 4) applicability to inert pollutants and those subject to linear removal and chemical conversion mechanisms and 5) applicability for rough or complex terrain situations.

This document and a companion report prepared by SAI on the wind field module outline the proposed modeling system. Special emphasis is placed on a description of the key scientific modules which parameterized the transport, dispersion, chemical transformation, and removal processes necessary to meet the design objectives. These modules are described in sufficient detail to allow their evaluation by ARB.

Section Two of this document describes the overall design of the modeling system and briefly summarizes the capabilities of each of the four major components: 1) the input data processors, 2) the meteorological model, 3) the dispersion model and 4) the postprocessors. The individual preprocessing programs are described in Section Three. Section Four contains a summary of the SAI recommendations for the wind field module and a description of the micrometeorological module. Each of the major modules composing the dispersion model is described in Section 5. Finally, Section 6 discusses the display and analysis capabilities of the postprocessors.


For questions regarding this research project, including available data and progress status, contact: Heather Choi at (916) 322-3893

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