Table of Contents - The Atmospheric Studies Group at TRC

Section 9: CALPUFF
Table 9-3 (Continued)
Control File Inputs - Input Group 3
Species List
Input Group 3 consists of two parts. The first part contains a list of species names and a table with four
integer flags for each species. These flags indicate if a pollutant is modeled (0=no, 1=yes), emitted
(0=no, 1=yes), dry deposited (0=no, 1=yes, treated as a gas with the resistance model, 2=yes, treated as a
particle with the resistance model, or 3=yes, user-specified deposition velocities used), and if the species
is to be added to group for output by specifying a group number greater than zero. The second part
allows one to name the output species groups, if any are identified in the table.
However, the user must first specify the species names to be modeled. Each species is entered on a
separate line with ! CSPEC = XXX ! !END!, where XXX is a species name (up to 12 characters in
length), and the variable delimiter and group delimiter (!END!) appears on the line. For example, a fivespecies
SO x , NO x run with MCHEM=1 would be:
INPUT GROUP: 3a, 3b -- Species list
-------------------
-------------
Subgroup (3a)
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! CSPEC = SO2 ! !END!
! CSPEC = SO4 ! !END!
! CSPEC = NOX ! !END!
! CSPEC = HNO3 ! !END!
! CSPEC = NO3 ! !END!
The MESOPUFF II chemical transformation option (MCHEM=1) in CALPUFF is designed to simulate
the conversion of SO 2 → SO = 4 and NO x → HNO 3 NO − 3. For this option, five pollutants in CALPUFF are
labeled as SO 2 , SO = 4, NO x , HNO 3 , and NO − 3. If the RIVAD/ARM3 transformation option (MCHEM=3) is
selected, NO and NO 2 are explicitly treated, and six pollutants are labeled as SO 2 , SO = 4, NO, NO 2 , HNO 3 ,
and NO − 3. However, by setting the appropriate flags controlling the various technical options (chemical
transformation, deposition, etc.), other reactive or non-reactive pollutants can be simulated.
The user has control over which species are to be emitted and dry deposited in a particular run. If the dry
deposition flag is set equal to 3 for any pollutant, a file called VD.DAT must be made available to the
model. This file contains a diurnal cycle of 24 user-specified deposition velocities for each pollutant
flagged.
The last species in (3a) must be 'BCON' when using the boundary condition option (MBCON > 0).
Species BCON does not participate in any chemical transformation mechanism and it should typically be
modeled without removal. Mass is placed in species BCON when generating boundary condition puffs so
that ‘clean’ air entering the modeling domain can be simulated in the same way as ‘polluted’ air.
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