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CAM nudging with monthly data

Bing

Bing
New Member
Dear all,

is it possible to do nudging with monthly target data at each model step? How to prepare the targe data file, one month per file? (I am interested in very long-term processes)

According to the user guide, Nudge_Times_Per_Day sets the number of target files per day. The minimum frequency is one day.
I can expand my monthly data to daily data and do the nudging. But then the target data will take up a lot of space because I am doing a long time run.

If anyone has experience with nudging using monthly data, please let me know.

Thanks in advance.

Best regards,
Bing
 

Bing

Bing
New Member
-------- an update ----------

I store all the monthly target fields in one file, say CAM_fv09.cam6.i.196901_197412.nc.

In the file, Dec-Jan-Feb & JJA months have valid variable values, while other months are filled with zeros. I intend to nudge for DJF & JJA months only.

Namelist is set as follows.

&nudging_nl
Nudge_Model =.true.
Nudge_Path ='/work/cesm_scripts_data/nudging/heat_forc_1/nudge_data/output/'
Nudge_File_Template='CAM_fv09.cam6.i.196901_197412.nc'
Nudge_Force_Opt = 1
Nudge_Times_Per_Day= 1
Model_Times_Per_Day= 48
Nudge_Ucoef =0.00
Nudge_Vcoef =0.00
Nudge_Tcoef =1.00
Nudge_Qcoef =0.00
Nudge_PScoef =0.00
Nudge_Beg_Year =1969
Nudge_Beg_Month=1
Nudge_Beg_Day =1
Nudge_End_Year =1972
Nudge_End_Month=12
Nudge_End_Day =31
/

The model runs without error. The results show that the model has been nudged at each time step, but to the target field of the first month of 1969. This means that the model only uses the data from the first time step, no matter how many time steps there are in the target data file.
 
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