WRF ideal cases - modifiy ZNT

[Joran]

Hello,

I would like to run WRF with an ideal case configuration (em_les) with the MYNN PBL scheme. I've tried changing this variable in the phys/module_physics_init.F file and then recompiling but nothing changes.

Here is my namelist.input.
Can you help me?
Thanks in advance!

Joran

 

[kwerner]

Hi Joran,
1) When you run the case with MYNN PBL turned on in the namelist, and then without MYNN PBL, do you see a difference?
2) Specifically, which variable are you changing in module_physics_init.F? Can you attach the file you modified?
3) Which version of WRF are you running?

 

[Joran]

Hi Joran,
1) When you run the case with MYNN PBL turned on in the namelist, and then without MYNN PBL, do you see a difference?
2) Specifically, which variable are you changing in module_physics_init.F? Can you attach the file you modified?
3) Which version of WRF are you running?

Hello,
I've just tried to run a simulation without MYNN PBL. The ZNT values are slightly different but do not correspond to what I want. The Z0 values remain the same.
The WRF version is v4.6.1.
Here is the module_physics_init.F file. I have modified the ZZWTR and ZZLND values (lines 1074-1075).

 

[kwerner]

Hi,
Thanks for the response. I just tested this, using wrfv4.6.1, your namelist.input file, and your modified module_physics_init.F file. I ran a test with the default code, and then the exact same test with the modified code, and I am actually seeing some very minor differences in the ZNT value between output files at the same time, in the same i,j grid - both at the initial time (which shows values of 0.0001, compared to 0.0006), and one hour into the simulation. See the screenshots.

 

[Joran]

Hi,
Thanks for the response. I just tested this, using wrfv4.6.1, your namelist.input file, and your modified module_physics_init.F file. I ran a test with the default code, and then the exact same test with the modified code, and I am actually seeing some very minor differences in the ZNT value between output files at the same time, in the same i,j grid - both at the initial time (which shows values of 0.0001, compared to 0.0006), and one hour into the simulation. See the screenshots.

Hello,
Thank you for your reply.

I made the same observation but the difference after one hour is very small. I would like to have a ZNT of about 0.006 for the whole time step. Is it possible to force WRF to adopt this behaviour?

 

[kwerner]

I spoke to a physics specialist colleague who said that the "ZZ*" variables are not actually used. You have to go into LANDUSE.TBL and look for the LW12 landuse section and edit SFZ0 there. The units are in cm. The default XLAND = 1 for land. If you want water, use the namelist for the "shalconv" LES case for guidance.