Science Inventory

OBJECTIVE REDUCTION OF THE SPACE-TIME DOMAIN DIMENSIONALITY FOR EVALUATING MODEL PERFORMANCE

Citation:

Gego, E. L., P. S. Porter, C. Hogrefe, A B. Gilliland, J L. Swall, J. S. Irwin, AND S T. Rao. OBJECTIVE REDUCTION OF THE SPACE-TIME DOMAIN DIMENSIONALITY FOR EVALUATING MODEL PERFORMANCE. Presented at 27th NATO/CCMS International Technical Meeting on Air Pollution Modeling and its Application, Banff, Canada, October 25-29, 2004.

Impact/Purpose:

The goal of this task is to thoroughly characterize the performance of the emissions, meteorological and chemical/transport modeling components of the Models-3 system, with an emphasis on the chemical/transport model, CMAQ. Emissions-based models are composed of highly complex scientific hypotheses concerning natural processes that can be evaluated through comparison with observations, but not validated. Both performance and diagnostic evaluation together with sensitivity analyses are needed to establish credibility and build confidence within the client and scientific community in the simulations results for policy and scientific applications. The characterization of the performance of Models-3/CMAQ is also a tool for the model developers to identify aspects of the modeling system that require further improvement.

Description:

In the United States, photochemical air quality models are the principal tools used by governmental agencies to develop emission reduction strategies aimed at achieving National Ambient Air Quality Standards (NAAQS). Before they can be applied with confidence in a regulatory setting, models' ability to simulate key features embedded in the air quality observations at an acceptable level must be assessed. With this concern in mind, the U.S. Environmental Protection Agency (EPA) has recently completed several executions of the Community Multiscale Air Quality model (CMAQ) and the Regional Modeling System for Aerosols and Deposition model (REMSAD) to simulate air quality over the contiguous United States during year 2001 with a horizontal cell size of 36 km x 36 km. The meteorological model MM5 and the emission processor SMOKE were used to generate the input fields necessary for CMAQ and REMSAD. See Hogrefe et al (2004a) and Eder and Yu (2004) for more information about model settings.

The research presented here was performed under the Memorandum of Understanding between the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) and under agreement number DW13921548. This paper has been reviewed in accordance with the EPA's peer and administrative review policies and approved for presentation and publication.

Record Details:

Record Type: DOCUMENT (PRESENTATION/PAPER)
Product Published Date: 10/27/2004
Record Last Revised: 06/21/2006
Record ID: 88696

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LABORATORY

ATMOSPHERIC MODELING DIVISION

MODEL EVALUATION AND APPLIED RESEARCH BRANCH