AEPA Community Multiscale Air Quality Modeling System: Models-3 U.S. Environmental Protection Agency Addressing Today's Air Pollution Problems Community Multiscale Air Quality Modeling System Regional and global coordinated efforts are needed to address environmental problems that are growing in complexity and scope. The models used to assess these problems and evaluate alternative solutions are increasing in complexity. Thus the concept of an integrated modeling and analysis framework, Models-3, was formulated. Models-3 is not a single model or modeling system, but rather it is a problem solving system of components that help build, evaluate, and apply air quality models. The initial version of Models-3 contains a Community Multiscale Air Quality (CMAQ) modeling system for urban to regional scale air quality simulation of tropospheric ozone, acid/nutrient deposition, visibility, and fine particulates. Models-3 will allow integration of the scientific and technology advancements of other federal agencies, academia, and research institutions, and thereby allow a more unified and comprehensive approach to environmental modeling. CMAQ Release and Evaluation A new version of the Models-3/CMAQ modeling system has been released for the Windows NT computer system, providing access to users who wish to accomplish integrated air quality modeling. New software will simulate the emissions, transport, chemical and physical transformation, and wet and dry deposition of atmospheric mercury. CMAQ's "one atmosphere" approach involving comprehensive multi-pollutant simulation is well suited to the study of atmospheric mercury cycling and environmental assessments. Additionally, an operational evaluation of Models-3/CMAQ for ozone has been completed and the modeling system recommended for widespread use. Ozone Bw* C**t PM2.S But C«m Ozone Difference (Control-Base) Eifed of 50% HOx reduction Ozone 50% NOx reduction Ozone Base Cs.se PM2.5 Cesa 7E July 14.19951:00:00 Min= 19 at 152,2], Mix = 1S3 at [31.50) PM 2.5 50% NOx reduction PM25 Difference Effect of 50% HOx reduction 69 ------- Models-3 Community Multiscale Air Quality Modeling System 1 Benefits Integrated modeling system that combines air pollutants into a multiscale "one atmosphere" structure - greatly enhancing the ability to understand spatial behavior of pollutants. Increase understanding of interactions between various pollutants. Can be used on the personal computer, thus allowing use by many scientific and air quality managers. Measures the effectiveness of controlling emissions, and allows for more meaningful ways by which regulatory strategies may be addressed. Purpose Supports EPA's efforts to improve the management community's ability to evaluate and assess impacts of air quality management practices for multiple pollutants at multiple scales. Provides a tool that improves scientist's ability to better probe, understand, and simulate chemical and physical interactions in the atmosphere. Accomplishments Modeling system released for Windows NT systems. • Publications include: Models-3 CMAO CB4 Tutorial for Windows NT; System Installation and Operation Manual for the EPA Third-Generation Air Quality Modeling System for Windows NT, and Science Algorithms of the EPA Models-3 CMAO Modeling System. Completion of an operational evaluation for ozone. Extension of the modeling system to atmospheric mercury. Participant U.S. EPA, Office of Research and Development, National Exposure Research Laboratory, Atmospheric Modeling Division, Research Triangle Park, NC. Models-3/CMAQ Release Evaluation of Models-3/CMAQ \ for Windows NT for Ozone itjp *For computational framework information, 'Contact: Robin L. Dennis National Eip-u,. R...arch L,b,r,^ contact: Sharon LeDuc dennis.robin@epa.gOv leduc. sharon@epa. gov 'For CMAQ modeling system information. Extension of Models-3/CMAQ rOr More contact: Daewon Byun to Atmospheric Mercury Information: bvun.daewon@epa. gov •Contact: Russell Bullock bullock.russell@epa.gov For more information on this and other NERL science projects, visit our Website http://www.epa.gov/nerl/ WEBSITE ANNOUNCEMENT March 2001 ------- |