Table of Contents - The Atmospheric Studies Group at TRC

Section 9: CALPUFF
Table 9-5 (Concluded)
CALMET.DAT file - Data Records
Record
Type
Variable
No.
Variable
Name
Type a
Description
15 1 CLABPC char*8 Variable label ('IPCODE')
15 2,3 NDATHRB,
NSECB
15 4,5 NDATHRE,
NSECB
integer
integer
Year, Julian day and hour (YYYYJJJHH) and seconds
(SSSS)
Year, Julian day and hour (YYYYJJJHH) and seconds
(SSSS)
15 6 IPCODE integer
array
Precipitation type code
0 - no precipitation
1 to 18 - liquid precipitation
19 to 45 - frozen precipitation
a char*8 = Character*8
9.2.2 ISCMET.DAT
CALPUFF can be driven by a single-station standard ISC3-type of meteorological file, compatible with
the earlier ISC2 version of the model, or an augmented ISC3-type of meteorological file. In addition, the
ISCMET.DAT file used by CALPUFF can accommodate an extended data record that includes the
augmented ISC3 data plus variables not found in either a standard ISC3 data record, or the augmented
ISC3 data record. This extended ISC3-type data file format has been modified further to allow subhourly
time steps. In the description to follow, we refer to the standard ISC3 file as the "base" ISC3
format.
CALPUFF is normally run with a full three-dimensional wind field and temperature field, as well as twodimensional
fields of mixing heights and other meteorological variables (see CALMET.DAT in Section
9.2.1). However, in some near-field applications, when spatial variability of the meteorological fields
may not be significant (e.g., uniform terrain and land use), the single-station data file may be used. The
model uses the data in the ISCMET.DAT file to fill the 2-D or 3-D arrays with the scalar values read from
the file. In single-station mode, CALPUFF assigns the single value of each variable read from the
ISCMET.DAT file to all grid points, resulting in a spatially uniform gridded field. However, the model
does not assume that the meteorological conditions are steady-state, which allows the important effects of
causality to be simulated even with the single-station meteorological data. For example, the time required
for plume material to reach a receptor is accounted for in the puff formulation, and curved trajectories and
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