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Cloud optical thickness output (TAUCLDI and TAUCLDC) is always 0

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T

todor_Gai

New member
Hello,
for some time I am trying to obtain data for cloud optical thickness from wrf model.
However, the output values for the TAUCLDI (CLOUD OPTICAL THICKNESS FOR ICE) and TAUCLDC (CLOUD OPTICAL THICKNESS FOR WATER) are always 0. As far as I know this means that the model is not computing these values.
I've tried different parameters in the &physics block in namelist.input but still cannot understand what I am missing.
I am using data from GFS 0.25 data for initial conditions.
Is it possible that the model needs some additional data to calculate the thickness output ?
Can somebody help me understand what I am doing wrong ?
I am using v4 of the WRF model and these are the physics configs:
Code: 
&physics                 
mp_physics               = 7,        7,
use_aero_icbc            = .true.,
use_rap_aero_icbc        = .true.,
aer_opt                  = 2,
aer_aod550_opt           = 1,
aer_aod550_val           = 0.12,
aer_angexp_opt           = 1,
aer_angexp_val           = 1.7,
aer_ssa_opt              = 1,
aer_asy_opt              = 1,
shcu_physics             = 2,        2,
ra_lw_physics            = 5,        5,
ra_sw_physics            = 5,        5,
radt                     = 30,       30,
bl_mynn_edmf             = 0,        0,
sf_sfclay_physics        = 5,        5,
sf_surface_physics       = 2,        2,
bl_pbl_physics           = 5,        5,
bldt                     = 0,        0,
cu_physics               = 1,        1,
cudt                     = 5,        5,
isfflx                   = 1,
ifsnow                   = 0,
icloud                   = 1,
surface_input_source     = 1,
num_soil_layers          = 4,
sf_urban_physics         = 0,        0,
maxiens                  = 1,
maxens                   = 3,
maxens2                  = 3,
maxens3                  = 16,
ensdim                   = 144,
/

Thank you in advance
Todor
 
Todor,
These two variables should have valid values for Goddard radiation scheme, which is what you activated based on your namelist.
I wonder whether you have modified Registry.EM_COMMON, changing the following two lines from:

state real taucldi ikj misc 1 - r "TAUCLDI" "CLOUD OPTICAL THICKNESS FOR ICE" ""
state real taucldc ikj misc 1 - r "TAUCLDC" "CLOUD OPTICAL THICKNESS FOR WATER"

to

state real taucldi ikj misc 1 - rh "TAUCLDI" "CLOUD OPTICAL THICKNESS FOR ICE" ""
state real taucldc ikj misc 1 - rh "TAUCLDC" "CLOUD OPTICAL THICKNESS FOR WATER"

Then recompile and rerun the case. Please also use the newer version of WRF (e.g., WRFv4.2)
 
Hi,
yes I have modified the lines that you've mentioned in the same way but the values of TAUCLDI and TAUCLDC are always zero for each point, each time.
I tried the model with that config at different times of the year but the result is always the same. And that makes me think that the model is not calculating the values. Also I hardly find any information about these properties on the web and the model setup for them.
I will be extremely grateful if somebody share some resources.

P.S.
Also I've checked and I am using the latest version WRF and it is 4.2 .

Ming Chen said:
Todor,
These two variables should have valid values for Goddard radiation scheme, which is what you activated based on your namelist.
I wonder whether you have modified Registry.EM_COMMON, changing the following two lines from:

state real taucldi ikj misc 1 - r "TAUCLDI" "CLOUD OPTICAL THICKNESS FOR ICE" ""
state real taucldc ikj misc 1 - r "TAUCLDC" "CLOUD OPTICAL THICKNESS FOR WATER"

to

state real taucldi ikj misc 1 - rh "TAUCLDI" "CLOUD OPTICAL THICKNESS FOR ICE" ""
state real taucldc ikj misc 1 - rh "TAUCLDC" "CLOUD OPTICAL THICKNESS FOR WATER"

Then recompile and rerun the case. Please also use the newer version of WRF (e.g., WRFv4.2)
Click to expand...
 
Hi,
I think I found a solution. In case somebody else has the same problem I tried with the CAM (code 3) scheme both for ra_sw/lw_physics.
With this scheme I got non-zero values for the properties.

Now I have to check if the values are correct.
If somebody has an idea how to do that, I will be very grateful.

Thank you
 
Thanks for the kind post. Hope it is helpful for other users.
However, these variables should be calculated in goddard and cam radiation schemes. I am not sure why they are zero in goddard. We will take a look at this issue.
 
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