What is the expected number/types of WRF/MCIP soil categories in CMAQ

The LSM_MOD.F script file at CMAQ_REPO/CCTM/src/depv/m3dry/LSM_MOD.F has this information about soil types:

The corresponding LSM_MOD.F code at CMAQ_REPO/CCTM/src/depv/stage/LSM_MOD.F has this information:

I am trying to understand how soil category properties are allocated in CMAQ, and have these questions:
Question 1a) Under m3dry deposition scheme, is CMAQ setting soil categories = 16 for WRFv4 and soil categories = 11 for WRFv3, irrespective of LSM used in WRF?
Question 1b) There are capitalized soil category property variables (e.g. WWLT_WRFV3(N_SOIL_TYPE_WRFV3), WWLT_WRFV4P(N_SOIL_TYPE_WRFV4P) ) and small letter counterparts (e.g. wwlt( : )). What/where is the latter used for in CMAQ?
Question 2) Under CMAQ stage dry deposition scheme, I am seeing 11 categories for WRFv3 with PX, 16 categories for WRFv4 with PX LSM, 19 categories of soil property for CLM and NOAH unaffected by WRF version. Am I understanding this correctly?
Question 3a) My MCIP files show 16 SLTYP values (I used WRF v3 with NOAH LSM, NLCD40 LU) which seems inconsistent with the 11 categories under m3dry as well as the 19 in stage model - what am I missing here?
Question 3b) There is a set of MCIP files in the CMAS repository (Output - Google Drive used PX LSM with NLCD in WRFv3) with 14 SLTYP categories. Again, 14 seems to be different from soil categories in both m3dry and stage models, and I cannot figure out why these MCIP soil categories are diffrent from those in CMAQ code?

In the STAGE deposition option, the mapping from the LSM_MOD.F data tables happen in ASX_DATA_MOD.F from lines 484 to 537. The code is currently set up to model all the possible NOAH and CLM soil texture categories in WRF4. If WRF is run with a smaller number of categories, only those are used. These data were taken from the WRF SOILPARM.TBL under the WRF4/WRF_BASE/run directory.

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Q1a: What you say is correct but the model was designed for PXLSM in particular. If NOAH or CLM were used and a soiltype for a land grid cell is > 16, it might bomb. Note that I think that MCIP will limit the number of soiltype to 16. If using NOAH set WRF_V4P = .TRUE. regardless of wrf version
Q1b: The variables wwlt, wfc, wsat etc… are the variable actually used in the dry deposition and bidi codes. Upper and lower case are meaningless.
Q2: see Jesse’s reply.
Q3a: In this case you should set WRF_V4P = .TRUE., Should work
Q3b: I don’t know

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Thanks @jbash and @pleim.jon . I wanted to make sure I got the code right - did you suggest setting WRF_V4P to .TRUE. in CCTM/scripts/BLD_CCTM_v533_intel/RUNTIME_VARS.F file?


By default WRF_V4P = .FALSE. but if it finds WRF_VERSION set to GE 4.1 it will change it to .TRUE.
So if you change the default setting at line 102 to:
it will always use that