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WRF4.0 hybrid vertical coordinate output

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Hi there,

I am using WRF4.0 now, with the hybrid vertical coordinate, I want to use the pressure in each level (p+pb) and the eta value of the boundary of each level(ZNW) to calculate the boundary pressures of each layer.
I checked the Registry.hyb_coord file and knew that the new equation is that:
Pd(i,j,k) = C3(k)*(Pds(i,j)-Pt)+C4(k)+Pt
My question is: how can I get the two constants C3 and C4, which also is indicated as C3H/C4H/C3F/C4F in the file, from the output of WRF.

Thanks in advance,
Hi Kezhen,
I apologize for the delay. We have all been out of the office for the holidays. The variables C3F/C3H/C4F/C4H should already be in the wrfout output. They are 2d variables. If you use something like 'ncview,' you should be able to click on the '2d vars' tab and see them listed, which also means you should be able to extract them from the wrfout* files.

Hi Kelly,

Thank you!
I used the command 'ncdump -h' trying to get a look for variables from wrfout* files, but I could only find the variable ZNU and ZNW which represent the eta values, I could not find the variable represents C3H/C3F/C4H/C4F.
For I could not find the variables I tried some names, like 'C3H', 'c3h', but it didn't work in NCL:
f = addfile(filename,"r");
c1 = f->C3H
;c1 = f->c3h

It always reported error: variable (C3H/c3h) is not in file.
Do you know why the constants didn't show up when I use 'ncdump -h' command ? How can I extract the C3H/C3F/C4H/C4F from wrfout* files in NCL?
Or do I need to turn on the output of C3H/C3F/C4H/C4F, how to turn on the output of it? Although I don't think I have turned it off before and it should be in the default output.

Thank you,
1) Are you running the basic WRFV4.0 code without any sort of modifications?
2) Can you attach your namelist.input file and your configure.wrf file so that I can see what settings you're using?

Hi Kelly,

I am not using basic WRF4.0 code but I managed to output these variables.

Thanks a lot!
That is great news. I'm very glad to hear that you got past the problem. Do you mind letting us know how you resolved the problem so that we can refer to this post for any future users who may have this problem?

Hi Kelly,

Sorry for replying late.
As you said before, C3H/C3F/C4H/C4F should already be in the output by default, and they are in the wrfout* files directly from WRF.
I calculated the half-hour mean of the output from wrfout* files but forgot to add these variables in my calculation process, so they didn't show up in my wrfout* files. I mistook the wrfout* as the original output from WRF, sorry for the trouble.

Thank you,