Modified the VEGPARM.TBL/MPTABLE.TBL and the results didn't change

[XCWei]

Hello, all!,

I am new to WRF and am currently trying to perform some experiments by modifying the VEGPARM.TBL and MPTABLE.TBL. However, no matter what modification I made, the results of the simulation are the same.

My procedure for replacing albedo is as follows:

• I modified the TBL file
  • Experiment 1: modified the RGL in MPTABLE.TBL.
  • Experiment 2: modified the EMISSMIN/EMISSMAX in VEGPARM.TBL.
  • Experiment 3: modified the Z0MIN/Z0MAX in VEGPARM.TBL.
• Finally, I ran real.exe and wrf.exe to perform the simulations.

Below is the relevant part of the &physics section in my namelist.input:

/
&physics
physics_suite = 'CONUS'
mp_physics = 8, 8,
cu_physics = 10, 10,
ra_lw_physics = 4, 4,
ra_sw_physics = 4, 4,
bl_pbl_physics = 5, 5,
sf_sfclay_physics = 5, 5,
sf_surface_physics = 4, 4,
radt = 5, 5,
bldt = 0, 0,
cudt = 0, 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0,
cu_rad_feedback = .true.,
num_soil_layers = 4,
rdlai2d = .true.,
usemonalb = .true.,
iz0tlnd = 1,
swint_opt = 2,
isfflx = 1,
ifsnow = 1,
topo_wind = 1, 0, 0,
surface_input_source = 1,
/


What could be the reason why my simulation results haven't changed? Thank you very much for your time and help!

 

[kwerner]

Hi,
The reason why the changes to the VEGPARM.TBL for experiments 2 and 3 aren't changing anything is that the VEGPARM.TBL is not used with the NoahMP LSM. See this description for details.

As for the RGL change to MPTABLE.TBL, I'm not sure what's going on. Can you share your full namelist.input file, as well as the modified MPTABLE.TBL? Please also let me know which version of WRF you're using and whether you made any other code modifications. Thanks!

 

[XCWei]

Hi,
The reason why the changes to the VEGPARM.TBL for experiments 2 and 3 aren't changing anything is that the VEGPARM.TBL is not used with the NoahMP LSM. See this description for details.

As for the RGL change to MPTABLE.TBL, I'm not sure what's going on. Can you share your full namelist.input file, as well as the modified MPTABLE.TBL? Please also let me know which version of WRF you're using and whether you made any other code modifications. Thanks!

Thank you for your reply! I tried to modify the Z0MVT (decreased by 30% for type7, 8, 9, 10 ), HVT (decreased by 30% for type7, 8, 9, 10 ) and RGL in the MPTABLE.TBL but their result still remain the same....

Below is my namelist:


&time_control
run_days = 10,
run_hours = 0,
run_minutes = 0,
run_seconds = 0,
start_year = 2020, 2020,
start_month = 12, 12,
start_day = 11, 11,
start_hour = 00, 00,
end_year = 2020, 2020,
end_month = 12, 12,
end_day = 20, 20,
end_hour = 23, 23,
interval_seconds = 3600
input_from_file = .true.,.true.,
history_interval = 60, 60,
frames_per_outfile = 1, 1,
restart = .false.,
restart_interval = 360,
io_form_history = 2
io_form_restart = 2
io_form_input = 2
io_form_boundary = 2
/

&domains
time_step = 12,
time_step_fract_num = 0,
time_step_fract_den = 1,
max_dom = 2,
e_we = 93, 266,
e_sn = 93, 266,
e_vert = 61, 61,
dzstretch_s = 1.1
p_top_requested = 10000,
num_metgrid_levels = 38,
num_metgrid_soil_levels = 4,
dx = 25000,
dy = 25000,
grid_id = 1, 2,
parent_id = 1, 1,
i_parent_start = 1, 21,
j_parent_start = 1, 21,
parent_grid_ratio = 1, 5,
parent_time_step_ratio = 1, 1,
feedback = 1,
smooth_option = 0
sfcp_to_sfcp = .true.
use_surface = .true.
/

&physics
physics_suite = 'CONUS'
mp_physics = 8, 8,
cu_physics = 10, 10,
ra_lw_physics = 4, 4,
ra_sw_physics = 4, 4,
bl_pbl_physics = 5, 5,
sf_sfclay_physics = 5, 5,
sf_surface_physics = 4, 4,
radt = 5, 5,
bldt = 0, 0,
cudt = 0, 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0,
cu_rad_feedback = .true.,
num_soil_layers = 4,
rdlai2d = .true.,
usemonalb = .true.,
iz0tlnd = 0,
swint_opt = 2,
isfflx = 1,
ifsnow = 1,
topo_wind = 1, 0, 0,
surface_input_source = 1,
/

&fdda
/

&dynamics
hybrid_opt = 2,
w_damping = 1,
diff_opt = 1, 1,
km_opt = 4, 4,
diff_6th_opt = 2, 2,
diff_6th_factor = 0.12, 0.12,
base_temp = 290.
damp_opt = 3,
zdamp = 5000., 5000.,
dampcoef = 0.2, 0.2,
khdif = 0, 0,
kvdif = 0, 0,
non_hydrostatic = .true., .true.,
moist_adv_opt = 1, 1,
scalar_adv_opt = 1, 1,
gwd_opt = 1, 1,
/

&bdy_control
spec_bdy_width = 5,
spec_zone = 1,
relax_zone = 4,
specified = .true.
/

&grib2
/

&namelist_quilt
nio_tasks_per_group = 0,
nio_groups = 1,
/


Thank you so much for your help~!

 

[kwerner]

Thanks! Can you also share the MPTABLE.TBL with one of the modifications you tried? You can just attach the table - no need to paste it to the message.

 

[XCWei]

Thanks! Can you also share the MPTABLE.TBL with one of the modifications you tried? You can just attach the table - no need to paste it to the message.

Thanks! Attached please find the MPTABLE which I changed the Z0MVT (decreased by 30% for type7, 8, 9, 10 ). Thank you so much for your help!

 

[kwerner]

Thanks for sharing that. From which directory are you running wrf? I'm asking because the MPTABLE.TBL in the test/em_real directory links back to a table in the run directory. You can see this if, from test/em_real, you issue

ls -ls MPTABLE.TBL

If that's the case, are you modifying the MPTABLE.TBL in the test/em_real directory, or the one in the run/ directory? You may have already considered this, and are doing it correctly, but that could be one explanation for the lack of changes.

 

[XCWei]

Thanks for sharing that. From which directory are you running wrf? I'm asking because the MPTABLE.TBL in the test/em_real directory links back to a table in the run directory. You can see this if, from test/em_real, you issue

ls -ls MPTABLE.TBL

If that's the case, are you modifying the MPTABLE.TBL in the test/em_real directory, or the one in the run/ directory? You may have already considered this, and are doing it correctly, but that could be one explanation for the lack of changes.

Thanks for your reply! I copied the original ../WRF/run folder into several folders like ../WRF/runG1, ../WRF/runG2, etc., and modified the MPTABLE file in each of them separately. Is this approach valid?

 

[kwerner]

That should be valid, I think. If you go to one of the directories where you ran wrf, just issue the "ls -ls MPTABLE.TBL" command to make sure it's not linking to some other unmodified table.

 

[XCWei]

That should be valid, I think. If you go to one of the directories where you ran wrf, just issue the "ls -ls MPTABLE.TBL" command to make sure it's not linking to some other unmodified table.

yes it's not linking to other table....That's weird that the result didn't change...

 

[kwerner]

Agreed. I ran with the default MPTABLE and with your modified table and I did see a difference in the results. What tool are you using to compare the files? If you aren't already, can you try the 'diffwrf' tool that's available with the WRF code. To use it, copy it from the /wrf/external/io_netcdf directory, into the directory where you're running wrf. Then use it with this syntax:

./diffwrf wrfout-file-created-with-default-mptable wrfout-file-created-with-modified-mptable

Make sure to compare files with the same time stamp, and you may need to include the path to the file if they're in different directories. If the files are identical, the command returns nothing. If there are any differences, it will print that to the screen.