WRF 4.3 (solar_diagnostics=1) some mp schemes TAU_QC values 0

[sweetler]

Hi:
I am using WRF4.3 with WRF-solar to calculate cloud optical thickness. The values (TAU_QC, TAU_QI,TAU_QS) are reasonable with most schemes, like Thompson,P3 and WDM6， but the values are all 0 with some schemes,like MORRISON(mp_physics=10),Milbrandt(mp_physics=9)and CAM5.1(mp_physics=11).
Does anyone know why the values are 0, and how to make them also output the correct values?

Below is the &physics section of my namelist. The same namelist(except mp_physics) was used in each trial.
&physics
mp_physics=9,9,9,
cu_physics=0,0,0,
ra_lw_physics=4,4,4,
ra_sw_physics=4,4,4,
bl_pbl_physics=1,1,1,
sf_sfclay_physics=1,1,1,
sf_surface_physics=2,2,2,
radt = 10, 10, 10,
bldt = 0, 0, 0,
cudt = 0, 0, 0,
isfflx = 1,
ifsnow = 1,
icloud = 1,
surface_input_source = 1,
num_soil_layers=4,
num_land_cat= 21,
sf_urban_physics=0,0,0,

&diags
solar_diagnostics = 1,
/

Thank You!
-TianTian

 

[tjuliano]

Hi TianTian,

Thank you for your question.

The reason that you are seeing values of zero for the optical thickness variables when using some microphysics schemes is because they do not calculate the effective radius, which is required for the calculation of optical thickness.

As of WRFv4.3.1, here is a list of microphysics schemes that calculate effective radius. All of them calculate the effective radius for cloud, ice, and snow, with the exception of P3 and ISHMAEL, which calculate only the effective radius for cloud and ice.

• WSM3 (mp_physics==3)
• WSM5 (mp_physics==4)
• WSM6 (mp_physics==6)
• NU-WRF (mp_physics==7)
• Thompson (mp_physics==8)
• WDM5 (mp_physics==14)
• WDM6 (mp_physics==16)
• NSSL variants (mp_physics==17,18,22)
• WSM7 (mp_physics==24)
• WDM7 (mp_physics==26)
• Thompson Aerosol-Aware (mp_physics==28)
• P3 variants (mp_physics==50,51,52,53)
• ISHMAEL (mp_physics==55)

Hopefully this information helps,
Tim