Record Display for the EPA National Library Catalog


Main Title Continued research in mesoscale air pollution simulation modeling. Volume I, Assessment of prior model evaluation studies and analysis of model validity and sensitivity /
Author Liu, M. K. ; Whitney, D. C. ; Seinfeld, J. H. ; Roth., P. M. ;
Other Authors
Author Title of a Work
Liu, Mei-Kao.
Demerjian, Kenneth L.
CORP Author Systems Applications, Inc., San Rafael, Calif.;Environmental Sciences Research Lab., Research Triangle Park, N.C.
Publisher Environmental Sciences Research Laboratory ; National Technical Information Service,
Year Published 1976
Report Number EPA 600/4-76-016 A; SAI/EF75-23; EPA-68-02-1237
Stock Number PB-257 526
OCLC Number 220807158
Subjects Photochemical smog--Simulation methods. ; Air--Pollution--Simulation methods.
Additional Subjects Air pollution ; Atmospheric models ; Computerized simulation ; Data processing ; Validity ; Concentration(Composition) ; Mathematical models ; Numerical analysis ; Carbon monoxide ; Nitrogen oxides ; Ozone ; Sensitivity ; Photochemical reactions ; Physical properties ; Chemical properties ; Urban areas ; Assessments ; Modifications ; Diffusion ; Wind velocity ; Errors ; Airshed models ; Trajectory model ; Grid model
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
EJBD ARCHIVE EPA 600-4-76-016a Headquarters Library/Washington,DC 12/27/2011
NTIS  PB-257 526 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation xiv, 246 leaves : ill., map ; 28 cm.
This report summarizes three independent studies: an analysis of prior evaluative studies of three mesoscale air pollution prediction models (two trajectory models and one grid model), an examination of the extent of validity of each type of model, and an analysis of the sensitivity of grid model predictions to changes in the magnitudes of key input variables. The analysis of prior studies showed that the three models evaluated generally reproduced measured ground-level pollutant concentrations with less than acceptable accuracy. This outcome is the result partly of problems of inadequacies in the models themselves and partly of the nonrepresentativeness of the measurement data. In the validity study, the results indicate that numerical diffusion can introduce significant error in the grid model, whereas neglect of wind shear and vertical transport are most detrimental in the trajectory approach. The sensitivity analysis assessed the change in magnitude of predicted atmospheric pollutant concentrations due to variations in wind speed, diffusivity, mixing depth, radiation intensity, and emissions rate. The results of the sensitivity analysis showed that variations in these key input variables influence predictions according to the following order of decreasing influence: wind speed, emissions rate, radiation intensity, mixing depth, vertical diffusivity, and horizontal diffusivity. Moreover, the responses of CO and NO2 tend to vary linearly with the meteorological and emissions parameters, whereas those of NO and O3 tend to be nonlinear.
"EPA 600/4-76-016a." "May 1976." "68-02-1237." "Project Officer, Kenneth L. Demerjian." Includes bibliographical references (p. 242-245). Photocopy. Research Triangle Park, N.C. : US EPA,