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Altering WRF's initial conditions

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I'm running WRF 3.9 using ERA-Interim data (GRIB) as input.
I wonder what is the best way to alter the input data (as in pseudo global warming studies. E.g., change the vertical distribution of humidity, lapse rate).
I guess I can try to edit either the GRIB files or the intermediate files.
What do you think is better?
Can you recommend a simple way to do so?

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You can change the met_em file, suppose both the initial and boundary conditions need to change. Please see the utility that might be helpful for you:
Hi Ming Chen, thanks for the reply.

Would changing the met_em files be better (easier) than changing the wrfinput_d0* files?
If editing the wrfinput files is easier, do I need to edit the wrfbdy file as well? Would it make any sense?

OK, it seems more logical to change the met_em files.
However, now I've noticed I'm getting met_em for each time interval for each of the domains.
I thought I only need the initial met_em.d0*, and all time intervals for met_em.d01.
Is this correct?

If it is, it means that I only need to change those files...
So why am I getting met_em for all time intervals for all domains?

Attached are example namelist (WPS and input) files.



  • namelist.input
    4.7 KB · Views: 66
  • namelist.wps
    1.5 KB · Views: 63
For your case, I suggest to change all met_em files, because you probably need modification not only for wrfinput, but also wrfbdy. If you don't change wrfbdy, it means that only your initial condition is changed.
Hi Ming Chen:

How would you consider the memory of the previous value of the variable? Say, for T2M, it has effect on RH of course. And if I change T2M, how do I consider change RH? Do I need to change all variables in this context?
It depends on your specific case. You need to make reasonable changes and don't violate the basic laws of the atmospheric physics and dynamics.