Puff Models: Architecture

The basic architecture of the CALPUFF model is shown in the graphic at right (click to see full-sized). In this graphic, there is a meteorological pre-processor, CALMET, that works to prepare raw meteorological data for the CALPUFF model. Data for CALMET comes from a variety of sources, including the relatively "standard" MM5 (mesoscale meteorological) model.

The graphic also shows three different dispersion models: the KSP (kinematic-simulation-particle) model, the CALPUFF dispersion model, and the CALGRID photochemical grid model.

Post-processing is done by PRTMET, the post-processor for meteorological data, and CALPOST, the post-processor for the main CALPUFF model.

A more detailed description of the CALPUFF modeling system is shown below:

Main Models

CALMET	3-D diagnostic meteorological model.
CALPUFF	Non-steady-state transport, dispersion, and deposition model.

Meteorological Preprocessors

METSCAN	Performs QA checks on hourly surface meteorological data.
SMERGE	Combines and formats files of surface meteorological data to produce a single file for use in CALMET.
PXTRACT	Extracts precipitation data from NCDC data sets.
PMERGE	Processes and merges precipitation data to produce a single file for use in CALMET.
READ62	Processes NCDC upper air meteorological data to produce upper air files for CALMET.
CALMM5	Processes MM5 meteorological output data and creates an data file suitable for input into CALMET.

Geophysical Data Processors

TERREL	Combines and grids terrain data.
CTGCOMP	Compresses USGS land use data files.
CTGPROC	Processes and grids land use data.
MAKEGEO	Merges land use and terrain data to produce the geophysical data file for CALMET.
PRELND1	Land use processor for ARM3 data set.
OPTHILL	Develops hill-shape parameters for the sub-grid-scale terrain option in CALPUFF.

Postprocessors

CALPOST	Postprocessor for CALPUFF: performs visibility calculations, averages and summarizes concentrations and deposition fluxes, determines ranked concentration/flux/plume extinction values, creates list files and plot files.
PRTMET	Lists selected meteorological data from CALMET and creates plot files.
APPEND	Appends two or more CALPUFF concentration, wet flux, dry flux or relative humidity (visibility) files.
CALSUM	Sums and scales concentrations or wet/dry fluxes from two or more source groups from different CALPUFF runs.
POSTUTIL	Processes CALPUFF concentration and wet/dry flux files. Creates new species as weighted combinations of modeled species; merges species from different runs into a single output file; sums and scales results from different runs; repartitions nitric acid/nitrate based on total available sulfate and ammonia.

The graphic at left (click to see full-sized) shows a sample run from the puff model. In this animation, the largest emitters of SO2 are shown by the blue dots. Running over a 10-day period, the animation shows the concentration of SO2 with this scale: Yellow=0.5 ug/m3 Red=2.5 ug/m3 Green=5.0 ug/m3 Magenta=12.5 ug/m3 Cyan=25.0 ug/m3

Another interesting animated graphic at right (click to see full-sized) shows another sample run from a puff model. The blue arrows are wind vectors, showing the speed and direction of the wind. The animation shows the puffs of pollution (as concentrations) as they move from the point source (the black square) towards the downwind receptors. Notice the use of a photographic overlay of the modeling region.

The CALPUFF modeling system runs on a number of platforms, including Windows-based machines with a GUI (graphic user interface) input/output screen.

An interesting model description is available as a Adobe Acrobat PDF file. Of particular interest in this document is the "checklist" format of specific characteristics.