Frequently Asked Questions about NCAR Preprocessors and WRF-Chem

For general discussion and questions, please refer to the WRF-Chem Discussion Forum.

WRF-Chem fails with plume rise option turned on and wrffirechemi* files created by fire_emis
fire_emis uses FINN fire emissions as input to create wrffirechemi* files. These include the total fire emission strength, while the plume rise code expects only the smoldering emissions. As stated in the README on our Website, one has to set the namelist option scale_fire_emiss = .true. to have the total emissions scaled accordingly. This option only works for the MOZART mechanisms and WRF-Chem will error halt when used in combination with any other chemical option.

mozbc stops when creating chemical initial (IC) and boundary conditions (BC)
Make sure to have the global MOZART-4 model fields downloaded for the entire time period you are creating the WRF-Chem IC and BC for. You can check on the dates in the MOZART-4 files with the command:
ncdump -v date,datesec <MOZART-4 filename>
A common error is also to download the MOZART-4 files for a region only that does not fully cover the WRF-Chem domain.

fire_emiss mapping when using FINN version SAPRC99 for bioemiss_burn_opt=1

 wrf2fire_map = 'co -> CO', 'no -> NO', 'so2 -> SO2','nh3 -> NH3','no2 -> NO2',

               'ald -> 1.00*BALD+1.00*CCHO+0.50*METHACRO+1.00*MGLY+1.00*RCHO',
               'hcho -> 1.00*HCHO',
               'ora2 -> 1.00*CCO_OH+1.00*HCOOH',
               'hc3 -> 1.00*ALK2+1.11*ALK3+0.40*MEOH',
               'hc5 -> 0.97*ALK4',
               'hc8 -> 1.00*ALK5',
               'eth -> 1.00*ALK1',
               'ete -> 1.00*ETHENE',
               'olt -> 0.50*METHACRO+0.50*MVK+1.00*OLE1',
               'oli -> 1.00*OLE2',
               'tol -> 1.00*ARO1',
               'xyl -> 1.00*ARO2',
               'ket -> 0.33*ACET+1.61*MEK+0.50*MVK+1.61*PROD2',
               'csl -> 1.00*PHEN',
               'iso -> 1.00*ISOPRENE',
               'hono -> 1.00*HONO',
               'onit -> 1.00*RNO3',
               'lim -> 1.00*TRP1',
               'oc -> OC;aerosol',
               'bc -> BC;aerosol',
               'pm25 -> PM25 + -1.0*BC + -1.0*OC;aerosol',
               'pm10 -> PM10 + -1.0*PM25;aerosol'




ACOM | Atmospheric Chemistry Observations & Modeling