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How to modify inputdata in user_nl_docn?

zongjinQin

zongjin qin
New Member
Hi everybody, when I running CESM2.1.3 ( --res f09_f09_mg17 --compset 1850_CAM40_CLM50%SP_CICE%PRES_DOCN%DOM_MOSART_CISM2%NOEVOLVE_SWAV ),
I am going to use my own modified SST data to replace the original data of the model which is 'sst_HadOIBl_bc_0.9x1.25_clim_pi_c101028.nc'.
However, the variable SST_cpl and the variable SST_cpl_prediddle in 'sst_HadOIBl_bc_0.9x1.25_clim_pi_c101028.nc' are not so clear to me that I don't know which of them to replace my modified SST data with or both of them need to be replaced. Also, does my own modified SST data need to be interpolated to the same resolution as 'sst_HadOIBl_bc_0.9x1.25_clim_pi_c101028.nc'?
Besides, one more question, how should I turn off the chemistry module in CAM4?
Could anyone help me with that? I really appreciate if you could help !
 

Attachments

  • README.case.txt
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  • user_docn.streams.txt.prescribed.txt
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  • user_nl_docn.txt
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cacraig

Cheryl Craig
CSEG and Liaisons
Staff member
I'm sorry that your questions have not been answered. Have you been able to solve this yourself? If not, I will see if I can find someone to answer your questions.
 

hannay

Cecile Hannay
AMWG Liaison
Staff member
The model uses: SST_cpl while SST_cpl_prediddle is just there for information purpose.

The "diddling"is a procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies.

The SST and ICE are interpolated between the mid-month values by a linear interpolation. The variables used will be ice_cov/SST_cpl. They are obtained used the icesst tools. The Hurrell dataset is specifically created for use with CAM and include the "diddling" procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies. This follows the protocol for AMIP simulation described in: Taylor, K.E., D. Williamson, and F. Zwiers (2000): The sea surface temperature and sea-ice concentration boundary conditions for AMIP II simulations. PCMDI Report No. 60 and UCRL-MI-125597, Lawrence Livermore National Laboratory, Livermore, CA, 25 pp.
pdf file available at http://www-pcmdi.llnl.gov/publications/pdf/60.pdf
 

ohmpawat

ohmpawat chen
Member
The model uses: SST_cpl while SST_cpl_prediddle is just there for information purpose.

The "diddling"is a procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies.

The SST and ICE are interpolated between the mid-month values by a linear interpolation. The variables used will be ice_cov/SST_cpl. They are obtained used the icesst tools. The Hurrell dataset is specifically created for use with CAM and include the "diddling" procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies. This follows the protocol for AMIP simulation described in: Taylor, K.E., D. Williamson, and F. Zwiers (2000): The sea surface temperature and sea-ice concentration boundary conditions for AMIP II simulations. PCMDI Report No. 60 and UCRL-MI-125597, Lawrence Livermore National Laboratory, Livermore, CA, 25 pp.
pdf file available at http://www-pcmdi.llnl.gov/publications/pdf/60.pdf
Hi, Hannay.
Could you tell me the meaning of ice_cov? My understand is the percentage of sea-ice's aera in a grid. But I found that there are some negative. So I think I misunderstand the meaning. Thanks a lot!

Best,
ohmpawat
 

zongjinQin

zongjin qin
New Member
The model uses: SST_cpl while SST_cpl_prediddle is just there for information purpose.

The "diddling"is a procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies.

The SST and ICE are interpolated between the mid-month values by a linear interpolation. The variables used will be ice_cov/SST_cpl. They are obtained used the icesst tools. The Hurrell dataset is specifically created for use with CAM and include the "diddling" procedure that ensures that the monthly mean of the daily-interpolated SST anomalies matches the monthly SST anomalies. This follows the protocol for AMIP simulation described in: Taylor, K.E., D. Williamson, and F. Zwiers (2000): The sea surface temperature and sea-ice concentration boundary conditions for AMIP II simulations. PCMDI Report No. 60 and UCRL-MI-125597, Lawrence Livermore National Laboratory, Livermore, CA, 25 pp.
pdf file available at http://www-pcmdi.llnl.gov/publications/pdf/60.pdf
Thanks a lot for your answer, Hannay.
 

zongjinQin

zongjin qin
New Member
Hi, Hannay.
Could you tell me the meaning of ice_cov? My understand is the percentage of sea-ice's aera in a grid. But I found that there are some negative. So I think I misunderstand the meaning. Thanks a lot!

Best,
ohmpawat
When I modified the file "sst_HadOIBl_bc_1x1_2000climo_c180511.nc", I also noticed this problem. Some of the sea ice values in this file are negative. Since I need to replace the sea ice in this file with the sea temperature and sea ice in HadISST1_SST, it's unclear to me if this negative value has any effect.
 

ohmpawat

ohmpawat chen
Member
When I modified the file "sst_HadOIBl_bc_1x1_2000climo_c180511.nc", I also noticed this problem. Some of the sea ice values in this file are negative. Since I need to replace the sea ice in this file with the sea temperature and sea ice in HadISST1_SST, it's unclear to me if this negative value has any effect.
As far as I know, the negative is reasonable.
 
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