Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title CDM2: Climatological Dispersion Medel, Version 2.0 (on Diskette).
CORP Author Environmental Sciences Research Lab., Research Triangle Park, NC. Meteorology and Assessment Div.
Publisher Sep 97
Year Published 1997
Stock Number PB98-500051
Additional Subjects Software ; Air pollution sources ; Gaussian plume models ; Point sources ; Area sources ; Plumes ; Wind direction ; Wind velocity ; Stability ; Downwash ; Air pollution dispersion ; Ecological concentration ; Diffusion modeling ; Rural areas ; Urban areas ; Spatial distribution ; Algorithms ; Diskettes ; CDM2 model ; Climatological Dispersion Model ; Emission rate
Library Call Number Additional Info Location Last
NTIS  PB98-500051 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 12/22/1997
Collation 1 diskette
The program determines long-term (seasonal or annual) quasi-stable pollutant concentrations in rural or urban settings using average emission rates from point and area sources and a joint frequency distribution of wind direction, wind speed, and stability. The Gaussian plume hypothesis forms the basis for the calculations. Contributions are calculated assuming the narrow plume hypothesis, and involve and upwind integration over the area sources. Computations can be made for up to 200 point sources and 2500 area sources at an unlimited number of receptor locations. The number of point and area sources can be easily modified within the code. CDM2 is an enhanced version of CDM and includes the following options: 16 or 36 wind-direction sectors; stack-tip downwash; and gradual (transitional) plume rise. The user has a choice of seven dispersion parameter schemes. Optional output includes point and area concentration rises and histograms of pollutant concentration by stability class. CDM 2.0 is a preferred model for regulatory applications in simple urban terrain.