CALPUFF and Postprocessors

F.3 Point Source Emissions File With Arbitrarily Varying Emissions (PTEMARB.DAT)
The PTEMARB.DAT file contains point source emissions data for sources with detailed, arbitrarily
varying emissions parameters. In the PTEMARB.DAT file, values for the stack parameters and emission
rates can be specified for each time step in the run. Plume rise is computed within the CALPUFF model
for each source.
PTEMARB.DAT may be provided as either a sequential unformatted data file, or as a free-formatted
ASCII data file (see Table F-16 for an example). Both of these use the same record structure consisting
of four header records, followed by a set of data records containing time-invariant source information,
and a set of records for the time-varying data. The time-invariant records contain the stack height,
diameter, coordinates, building downwash flag, vertical momentum flux factor, one user-defined optional
descriptive code for each source, and controlling building heights and widths (36 values for every 10E)
for each source identified by the building downwash flag. The time varying emissions and stack
parameter data follow in subsequent records. One data record per source is required for each time period
(e.g.,usually at hourly intervals).
Multiple PTEMARB.DAT files may be provided if groups of sources possess very different timevariability.
For example, group 1 may require hourly data records for the entire simulation period, while
group 2 may produce emissions for only a few weeks during the simulation. Using a second file for
group 2 is more economical to prepare because a single data record can be used to prescribe a long period
with no (or constant) emissions. Each such file must cover the entire modeling period, no source may
appear in more than one file, and the species list must be identical among these files.
The data in the PTEMARB.DAT file are independent of the horizontal and vertical grid systems being
used in the model. The horizontal coordinates are specified in terms of the meteorological grid projection
(UTM or Lambert conformal coordinates). The vertical layers receiving the emissions of the source are
based on the plume rise of the source computed internally by the model. However, the PTEMARB.DAT
file does contain time-dependent data specifying the emission parameters for a particular time period.
NOTE: There are structural differences between the PTEMARB.DAT file accepted by the current
version of CALPUFF and that accepted by earlier versions, so anyone familiar with the previous versions
must be certain to review the contents of the next few pages! CALPUFF will test the variable VRS2
contained in the header of PTEMARB.DAT to see that it identifies the correct version. If the file uses an
older format, changing VRS2 to the correct value will disable this check, and the results of the CALPUFF
application may be in error. Do not use an “old” version of this data file unless you are certain that the
format is correct.
MAR 2006 – CALPUFF
F-117