How to read CLM intial condition file

[sirajkhan78@gmail_com]

Hi,

I normally use CAM for climate simulation and this is the first time I am working with CLM initialization. In my specific study, I am want to add some perturbation (EOF of soil moisture) to the soil moisture variable in CLM initial condition file. Looking at the ncdump information of following CLM initial condition file (or restart file) I found that this file is not on regular lat lon grid.

/inputdata/lnd/clm2/initdata/clmi.IQCN.1951-01-01_1.9x2.5_gx1v6_simyr1850_c091016.nc

I am wondering how to read this single column file in NCL or MATLAB for adding some perturbation.

Also which variable represent soil moisture in this file.

double H2OSNO(column) ;
H2OSNO:long_name = "snow water" ;
H2OSNO:units = "kg/m2" ;
double H2OSOI_LIQ(column, levtot) ;
H2OSOI_LIQ:long_name = "liquid water" ;
H2OSOI_LIQ:units = "kg/m2" ;
double H2OSOI_ICE(column, levtot) ;
H2OSOI_ICE:long_name = "ice lens" ;
H2OSOI_ICE:units = "kg/m2" ;

Siraj

 

[slevis]

There are indexes included in the file that help you convert the vector format to lat-lon.

I have a vague memory that certain indexes contain wrong data, but I do not know the details off hand. This info should be available under "known problems" or "known bugs" on the clm website.

Sam Levis

 

[sirajkhan78@gmail_com]

Hi Sam,

I tried to use the indices (col1d_lat and col1d_lon) given in initial condition file and displayed the spatial pattern of variable. The is issue is to add some spatial EOF perturbation on the column variable. These indices can only help to display the variable. Is there any FORTRAN code inside the model which can help me to figure out this issue or Is there a way to convert lat lon data to column data?

I will appreciate if you can help me to sort out this issue.

Siraj

 

[slevis]

Beyond the indices that I suggested, I'm not aware of anything else, so i think you will need to create such a tool yourself.

Sam