Noah vs Noah-MP for WRF-Lake in WRF v4.6.0: recommended configuration and sensitivity experiments

845968376

845968376

New member
Hello WRF community,

I am using WRF v4.6.0 with the WRF-Lake module enabled:

sf_lake_physics = 1, 1
My main interest is in selecting an appropriate land surface model and designing a sensitivity experiment to assess the impact of lakes.

Model configuration​

  • WRF version: 4.6.0
  • PBL scheme:

    bl_pbl_physics = 1, 1 ! YSU
  • Land surface model options:
    • Noah (sf_surface_physics = 2)
    • Noah-MP (sf_surface_physics = 4)
  • Lake physics:

    sf_lake_physics = 1, 1

Questions​

  1. When using WRF-Lake (sf_lake_physics = 1), which land surface model is generally recommended:
    • Noah (sf_surface_physics = 2), or
    • Noah-MP (sf_surface_physics = 4)?
  2. My scientific goal is to perform a sensitivity experiment comparing simulations with lakes enabled versus lakes removed:
    • Is Noah-MP a better choice for such experiments?
  3. If using Noah-MP:
    • Do I need to explicitly modify or link GEOGRID.TBL.ARW.noahmp?
    • Are there recommended &noah_mp namelist settings when combined with WRF-Lake?
  4. Are there any known caveats or incompatibilities when combining:
    • bl_pbl_physics = 1 (YSU) or bl_pbl_physics =5 （MYNN）
    • sf_surface_physics = 4 (Noah-MP)
    • sf_lake_physics = 1
5. as for my namelist.input,is there any obvious problem or any other better options-set?

&time_control
run_days = 1,
run_hours = 06,
run_minutes = 0,
run_seconds = 0,
start_year = 2024, 2024,
start_month = 09, 09,
start_day = 03, 03,
start_hour = 00, 00,
end_year = 2024, 2024,
end_month = 09, 09,
end_day = 04, 04,
end_hour = 06, 06,
interval_seconds = 3600,
input_from_file = .true., .true.,
history_interval = 15, 15,
frames_per_outfile = 1, 1,
restart = .false.,
io_form_history = 2,
io_form_restart = 2,
io_form_input = 2,
io_form_boundary = 2,
iofields_filename = "var_d01.txt", "var_d02.txt"
ignore_iofields_warning = .true.,
debug_level = 0,
/



&domains
time_step = 45,
time_step_fract_num = 0,
time_step_fract_den = 1,
max_dom = 2,
e_we = 177, 205
e_sn = 134, 199
e_vert = 50, 50,
p_top_requested = 5000,
num_metgrid_levels = 38,
num_metgrid_soil_levels = 4,
dx = 9000, 3000,
dy = 9000, 3000,
grid_id = 1, 2,
parent_id = 1, 1,
i_parent_start = 1, 55
j_parent_start = 1, 41
parent_grid_ratio = 1, 3
parent_time_step_ratio = 1, 3,
feedback = 0,
smooth_option = 0,
use_surface = .true.,
sfcp_to_sfcp = .true.,
/

&physics
mp_physics = 8, 8,
ra_lw_physics = 4, 4,
ra_sw_physics = 4, 4,
radt = 9, 9,
sf_sfclay_physics = 1, 1,
sf_surface_physics = 2, 2,
bl_pbl_physics = 1, 1,
bldt = 0, 0,
cu_physics = 1, 0,
cudt = 5, 5,
isfflx = 1,
ifsnow = 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0,
sf_lake_physics = 1, 1,
use_lakedepth = 1, 1,
lakedepth_default = 50.0, 50.0,
lake_min_elev = 5.0, 5.0,

/
&dynamics
w_damping = 1,
diff_opt = 2, 2,
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,
epssm = 0.1, 0.3,
scalar_adv_opt = 1, 1,
etac = 0.1
/

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

&namelist_quilt
nio_tasks_per_group = 0,
nio_groups = 1,
/


Thank you very much for your suggestions and experiences.

Best regards,
 
I apologize for the late answer. This is because we are busy with MPAS tutorial. Please see my answers below:
845968376 said:
Hello WRF community,

I am using WRF v4.6.0 with the WRF-Lake module enabled:

sf_lake_physics = 1, 1
My main interest is in selecting an appropriate land surface model and designing a sensitivity experiment to assess the impact of lakes.

Model configuration​

  • WRF version: 4.6.0
  • PBL scheme:

    bl_pbl_physics = 1, 1 ! YSU
  • Land surface model options:
    • Noah (sf_surface_physics = 2)
    • Noah-MP (sf_surface_physics = 4)
  • Lake physics:

    sf_lake_physics = 1, 1

Questions​

  1. When using WRF-Lake (sf_lake_physics = 1), which land surface model is generally recommended:
    • Noah (sf_surface_physics = 2), or
    • Noah-MP (sf_surface_physics = 4)?
Click to expand...
I would suggest you run with Noah. This is because we have tested lake module using Noah when we initially incorporated lake module into WRF.
845968376 said:
  1. My scientific goal is to perform a sensitivity experiment comparing simulations with lakes enabled versus lakes removed:
    • Is Noah-MP a better choice for such experiments?
Click to expand...
No, I don't think so. Lake impacts should be independent of LSM model.
845968376 said:
  1. If using Noah-MP:
    • Do I need to explicitly modify or link GEOGRID.TBL.ARW.noahmp?
    • Are there recommended &noah_mp namelist settings when combined with WRF-Lake?
Click to expand...
Yes you need to link GEOGRID.TBL.ARW.noahmp
Again, &noah_mp options should be independent of Lake module.
845968376 said:
  1. Are there any known caveats or incompatibilities when combining:
    • bl_pbl_physics = 1 (YSU) or bl_pbl_physics =5 （MYNN）
    • sf_surface_physics = 4 (Noah-MP)
    • sf_lake_physics = 1
Click to expand...
I don't think there are any incompatibilities. But YSU is a better option. Many updates have been put into MYNN since Lake module was coupled into WRF. I am not sure whether these updates introduce some issues.
845968376 said:
5. as for my namelist.input,is there any obvious problem or any other better options-set?


&time_control
run_days = 1,
run_hours = 06,
run_minutes = 0,
run_seconds = 0,
start_year = 2024, 2024,
start_month = 09, 09,
start_day = 03, 03,
start_hour = 00, 00,
end_year = 2024, 2024,
end_month = 09, 09,
end_day = 04, 04,
end_hour = 06, 06,
interval_seconds = 3600,
input_from_file = .true., .true.,
history_interval = 15, 15,
frames_per_outfile = 1, 1,
restart = .false.,
io_form_history = 2,
io_form_restart = 2,
io_form_input = 2,
io_form_boundary = 2,
iofields_filename = "var_d01.txt", "var_d02.txt"
ignore_iofields_warning = .true.,
debug_level = 0,
/



&domains
time_step = 45,
time_step_fract_num = 0,
time_step_fract_den = 1,
max_dom = 2,
e_we = 177, 205
e_sn = 134, 199
e_vert = 50, 50,
p_top_requested = 5000,
num_metgrid_levels = 38,
num_metgrid_soil_levels = 4,
dx = 9000, 3000,
dy = 9000, 3000,
grid_id = 1, 2,
parent_id = 1, 1,
i_parent_start = 1, 55
j_parent_start = 1, 41
parent_grid_ratio = 1, 3
parent_time_step_ratio = 1, 3,
feedback = 0,
smooth_option = 0,
use_surface = .true.,
sfcp_to_sfcp = .true.,
/

&physics
mp_physics = 8, 8,
ra_lw_physics = 4, 4,
ra_sw_physics = 4, 4,
radt = 9, 9,
sf_sfclay_physics = 1, 1,
sf_surface_physics = 2, 2,
bl_pbl_physics = 1, 1,
bldt = 0, 0,
cu_physics = 1, 0,
cudt = 5, 5,
isfflx = 1,
ifsnow = 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0,
sf_lake_physics = 1, 1,
use_lakedepth = 1, 1,
lakedepth_default = 50.0, 50.0,
lake_min_elev = 5.0, 5.0,

/
&dynamics
w_damping = 1,
diff_opt = 2, 2,
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,
epssm = 0.1, 0.3,
scalar_adv_opt = 1, 1,
etac = 0.1
/

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

&namelist_quilt
nio_tasks_per_group = 0,
nio_groups = 1,
/
Click to expand...
Is there any special reason you want to set etac=0.1? The default value is 0,2, which works as expected.
845968376 said:
Thank you very much for your suggestions and experiences.

Best regards,
Click to expand...
 
Hi Chen,

Thanks for your explanation.(y)

Regarding my last question — since my simulation region is the Tibetan Plateau, I checked this discussion on the NCAR forum about etac: Monotonically decreasing pressure
If I do not encounter the same issue as described in that thread, would it be better to set it to 0.2?
 
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