Advanced / Configuration Setup / Variables Not Set in the GUI

• CAPEMIN (-1) - defines the threshold value of CAPE (convective available potential energy J/kg) to initiate enhanced vertical mixing. A value of -1 (default = -1) skips the CAPE computation such that if CAPE is not available in the input meteorological data file then it is NOT computed. When the value is greater than zero, CAPE enhanced mixing is turned on and if CAPE is not available in the input data file, it is computed for each grid point, which may substantially slow down the overall calculation. CAPE enhanced mixing results in particles in the cloud-layer being randomly redistributed within the cloud-layer if they reside in a grid cell where CAPE exceeds CAPEMIN. A initial value of 500 J/kg is suggested to test this computation. Setting CAPEMIN to -2 will utilize the Grell convective parameterization if Grell convective fluxes are in the meteorological input files. Setting CAPEMIN to -3 will utilize the extreme convection parameterization.
  
• DECAY (1) - when (1=default) lets deposited material radioactively decay after accumulation on the deposition grid until it is written to the output file. When (0) then deposited material does not decay. In both situations, when the radioactive half-life is defined in the CONTROL file, the mass on the particles while airborne will decay in both cases. This flag only determines what happens after the material is deposited on the grid and before the information is written to the the output file.
  
• IVMAX (20) Number of variables written to PARTICLE_STILT.DAT when running in STILT mode (ICHEM = 8). Must equal the number of variables listed for variable VARSIWANT.
  
• K10M (1) - when (1=default) the 10m/2m values for winds and temperatures are used as the lowest data level if available in the meteorological file. When set to zero, these data values will not be used in any computations.
  
• KAGL (1) - KAGL only applies to trajectories, not concentration simulations. For trajectory simulations, the default option is to write the heights as AGL (KAGL=1), setting KAGL=0 converts the trajectory output heights to MSL. The KMSL namelist parameter only applies to how heights are interpreted in the CONTROL file, while KAGL determines how the model heights are written to the output file.
  
• KHINP (0) - when non-zero sets the particle age in hours that will be read from the particle initialization file (PARINIT) that may contain particles of many different ages each output time period. This option is intended to be used with continuous initialization (NINIT=2) in which the calculation is continued from a previous simulation in which particles older than KHINP had been terminated by using the namelist variable KHMAX=KHINP. These continuous emission simulations require particles to be added each time step. This configuration works best when the integration time step is set to the same fixed value for all simulations.
  
• KRAND (0) - same as KRAND=1 if NUMPAR is greater than 5000 or same as KRAND=2 if NUMPAR is less than or equal to 5000. KRAND=1 precomputes all the random numbers required for the particle turbulence calculations. KRAND=2 computes the random numbers at each dispersion time step. The dynamic method is slightly more accurate than the precomputed random numbers, but it requires about twice as much CPU time. With large particle release rates both methods will provide comparable results. The special case of KRAND=3 will result in no turbulent mixing being added to the particle position; the particle track will follow the mean trajectory. This option is primarily intended for diagnostic testing. The option KRAND=4 follows the STILT method of randomly selecting an initial seed number for the random number generator and compute these random numbers at each dispersion time step. KRAND=0, 1, 2, and 3 uses the same initial seed number for non-dispersion applications (i.e., emissions placement, deposition, chemistry) to allow simulations to be repeatable. KRAND=10, 11, 12, and 13 are the same as KRAND=0, 1, 2, and 3 except a random initial seed number is used for non-dispersion procedures. KRAND=4 also uses a random initial seed number for non-dispersion procedures.
  
• KWET (1) - when (1=default) the code uses the precipitation values in the defined meteorological input data file. When KWET=2, the code will try to open a file called raindata.txt which defines the directory, base, and suffix name of an external precipitation file that is in the ARL standard format. The text file also defines the 4-character name of the precipitation variable as well as the conversion factor from file units to model units (meters/min). The file name is automatically constructed from the prefix and suffix names using current calculation date following the convention: {prefix}{YYYYMMDD}{suffix}. If the raindata.txt file is not found in the startup directory, the model will create a template for manual editing and then stop.
  
• MAXDIM (1) - is the maximum number of pollutants that can be attached to one particle. Otherwise, if multiple pollutants are defined they are released as individual particles. This feature is only required with chemical conversion modules, which are not part of the standard distribution. However, the species 1->2 conversion option will automatically set MAXDIM=2, but the standard emissions routine will still put each species on a different particle in its appropriate array element. The only emissions routine that is enabled to release multiple species on the same particle is the emissions file option. Setting MAXDIM greater than one forces all the species on the same particle with the limitation that the number of defined pollutants must equal MAXDIM. No other combinations are permitted. The advantage of this approach is that not as many particles are required for the calculation as in the situation where every pollutant is on its own particle. The limitation is that each species on the particle should have comparable dynamic characteristics, such that they are all gases or have similar settling velocities, otherwise the transport and dispersion simulation would not be very realistic.
  
• MESSG (MESSAGE) - is the default base name of the diagnostic MESSAGE file. In normal simulations, the name defaults to the base name. In an ensemble multi-processor calculation, the message file name would be automatically set to correspond with the process number by appending the process number to the base name: {base}.{000}, where the process number can be any integer between 001 and 999.
  
• NBPTYP (1) - defines the number of bins assigned to each particle size as defined in the pollutant section of the CONTROL file. The default value of one uses the input parameters. A value larger than one will create that number of particle size bins centered about each value in the CONTROL file. The program creates the mass distribution for a range of particle sizes given just a few points within the distribution. We assume that dV/d(log R) is linear between the defined points for an increasing cumulative mass distribution with respect to particle diameter. The input points in the CONTROL file should be sorted by increasing particle size within the array. For instance, if the CONTROL file defines 3 particle sizes (5, 20, and 50), and NBPTYP=10, then for the 5 micron particle generates sizes from 2.3 to 8.1 microns while the 50 micron input particle generates sizes from 30.2 to 68.9 microns.
  
• NTURB (0) Turbulence on: 0; turbulence off: 1
  
• OUTDT (0) - defines the output frequency in minutes of the endpoint positions in the PARTICLE.DAT file when the STILT emulation mode is configured. The default value of 0 results in output each time step while the positive value gives the output frequency in minutes. A negative value disables output. The output frequency should be an even multiple of the time step and be evenly divisible into 60. In STILT emulation mode, the time step is forced to one minute.
  
• PINBC - defines the input particle file name (default=PARINBC) that can be used for boundary conditions during the simulation.
  
• PLRISE (1) Brigg's plume rise option (1), Sofiev plume rise option (2), or Freitas plume rise option (3) used when heat/fire radiative power in the emissions input file is nonzero.
  
• RHB (80) - defines the initial relative humidity required to define the base of a cloud.
  
• RHT (60) - the cloud continues upward until the relative humidity drops below this value. The values represent a compromise between the cases when the cloud (and precipitation) covers an entire grid cell and those situations where the cloud may only cover a fraction of the meteorological grid cell. For example, using the cloud fractions as defined in the EDAS (40 km resolution) data, 70% of the time 100% cloud cover occurs when the RH exceeds 80%.
  
• SEED (0) The value of the random seed is set to -1+SEED. Default value of SEED is 0, thus the default of the random seed for the single processor version is -1.
  TLFRAC (0.1) The fraction of the Lagrangian vertical time scale used to calculate the dispersion time step in the STILT dispersion scheme. This variable is used when the STILT dispersion scheme (IDSP = 2) is selected.
  
• TVMIX - vertical mixing scale factor is applied to vertical mixing coefficients when KZMIX = 2 for boundary layer values and KZMIX = 3 for free-troposerhere values.
  
• VARSIWANT ('TIME','INDX','LONG','LATI','ZAGL','SIGW','TLGR','ZSFC','TEMP','SAMT','FOOT','SHTF','DMAS','DENS','RHFR','SPHU','DSWF','WOUT','MLHT','PRES') List of variables written to PARTICLE_STILT.DAT when running in STILT mode (ICHEM = 8). The following variable options are available: TIME (time since start of simulation), SIGW (standard deviation of vertical velocity), TLGR (Lagrangian vertical time scale), LONG (longitude), LATI (latitude), ZAGL (height AGL), ZSFC (terrain height), INDX (particle index), ICDX (cloud index: 1=updraft; 2=environment; 3=downdraft), TEMP (temperature at lowest model layer), TEMZ (temperature), PRES (pressure), SAMT (time below VEGHT), FOOT (footprint), SHTF (sensible heat flux), WHTF (latent heat flux), TCLD (total cloud cover), DMAS (particle weight change), DENS (air density), RHFR (relative humidity fraction), SPHU (specific humidity), LCLD (low cloud cover %), ZLOC (limit of convection height), DSWF (downward shortwave radiation), WOUT (vertical mean wind velocity), MLHT (mixed layer height), RAIN (total rain fall rate m/min), CRAI (convective rain fall rate m/min), ZFX1 (vertical displacement due to convective flux).
  
• VBUG (0) - additional insect horizontal speed (m/s) added to trajectories.
  
• VDIST (VMSDIST) - an output file that contains the hourly vertical mass distribution, similar to the values shown in the MESSAGE file every six hours. The output can be disabled by setting the default file name to blank or null length. Programs vmsmerge and vmsread are available in the exec directory to view and process these files.
  
• VEGHT (0.5) Height below which particle's time is spent is tallied to create footprint written to PARTICLE_STILT.DAT when run in STILT mode (ICHEM = 8). Less than or equal to 1.0: fraction of PBL height; greater than 1.0: height AGL (m).
  
  
  

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