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Question about CPLMASK variable in wrfinput


New member
Hi all,

I am trying to run wrf v4.3.3 in coupled mode with the NEMO ocean model via the OASIS coupler. After running real.exe, I modify the wrfinput file with ncap2 -O -s "CPLMASK(:,0,:,:)=(LANDMASK-1)*(-1)" wrfinput_d01 wrfinput_d01. When the model runs, I get the following messages in rsl.out.0000:
checks on cplmask of external model domain: 1 minval(grid%cplmask(ips:ipe,jext,jps:jpe)): 0.0000000E+00 max of external model domain cplmask: 1 = 0 => no coupling between this external model domain and this WRF patch maxval(grid%cplmask(ips:ipe,jext,jps:jpe)): 0.0000000E+00
Note that in namelist.input, I have sst_update = 1 and num_ext_model_couple_dom = 1. Also, the CPLMASK variable in wrfinput looks like:
float CPLMASK(Time, num_ext_model_couple_dom_stag, south_north, west_east) ; CPLMASK:FieldType = 104 ; CPLMASK:MemoryOrder = "XYZ" ; CPLMASK:coordinates = "XLONG XLAT XTIME" ; CPLMASK:description = "COUPLING MASK (0:VALUE FROM SST UPDATE; 1:VALUE FROM COUPLED OCEAN), vertical di" ; CPLMASK:stagger = "Z" ; CPLMASK:units = "" ;
Does anyone know what could be wrong and the maximum CPLMASK value is not being recognized?

I would appreciate any suggestions!
Thanks in advance,
Hi John,
Once you make that modification to the wrfinput file, what values are you then seeing for CPLMASK - prior to running wrf?
Τhe CPLAMASK has a value equal to 1 in the sea area and zero in the land area of the domain. Αs an update to say that in the results of the wrf, the SST for example, seems to change correctly in the coupled region that defined by CPLMASK.. Is the problem only related to minval() and maxval() functions?
I would like to apologize for the long delay in response. I've been out of the office for the past week, and was busy with our WRF tutorial the week before that. Thank you for your patience.

It seems that the only issue is actually with the maxval, since you're expecting a value of 1, but are seeing 0 in that message. I don't have much experience with coupled models, but if you are seeing the correct results, then perhaps it's okay. Do all other values seem to be what you'd expect? If so, then I would say it's probably safe to continue.