Record Display for the EPA National Library Catalog

RECORD NUMBER: 3 OF 6

Main Title Implementation and Experimentation of an Advanced Land-Surface/PBL Model in the Penn State/NCAR Mesoscale Model (MM4).
Author Xiu, A. ; Pleim., J. E. ;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Research and Exposure Assessment Lab. ;MCNC, Research Triangle Park, NC. Information Technologies Div.
Publisher 1993
Year Published 1993
Report Number EPA/600/A-94/061;
Stock Number PB94-160421
Additional Subjects Atmospheric models ; Acid rain ; Meteorological data ; Mathematical models ; Evapotranspiration ; Soil water ; Flux rate ; Cloud cover ; Heat ; Atmospheric temperature ; Field tests ; Kansas ; Vegetation ; Mesometeorology ; Land surface planetary boundary layer models ; MM4 model
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Status
NTIS  PB94-160421 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 23p
Abstract
A more advanced land-surface/PBL model is implemented in the Penn State/NCAR Mesoscale Model Version 4(MM4) which is utilized to provide meteorological data to the Regional Acid Deposition Model (RADM). The diurnal evolution of the planetary boundary layer (PBL) and its dynamic characteristics are crucial to air quality modeling. The PBL is strongly dependent on surface fluxes of heat, moisture, and momentum. These fluxes are largely controlled by soil moisture and vegetative evapotranspiration. Previously, the MM4 was unable to respond to dynamic soil moisture conditions, leading to unrealistic partitioning of the surface energy budget between sensible and latent heat fluxes. The new model includes explicit soil moisture and evapotranspiration, as well as improved radiation and cloud cover algorithms, flux-profile relationships, and PBL mixing. The soil-vegetation-atmosphere transfer scheme is similar to the scheme developed for the French Weather Service mesoscale meteorological model. The PBL mixing scheme, a hybrid of eddy diffusion and nonlocal closure, is the same as is currently used in the RADM. The model has been previously tested in 1-D form against several field experiments and has demonstrated good agreement with measurements.