[MITgcm-support] a problem with EXF

[Matthew Mazloff]

Hi Ming,

The model does need a ustress value at every grid point and at every 
timepoint.  So the file must be like ustre(x,y,t1),ustre(x,y,t2)...  
There is an option to interpolate the exf files so you can give a coarse 
ustress field and have the model interpolate to your grid at each 
timestep, this would allow you to use vey small input files.  Currently 
this is only setup to work on a lat, long grid. 

You can check out
[MITgcm] / MITgcm_contrib / quarter_degree_global / input / data.exf
maybe this link will work:
http://mitgcm.org/cgi-bin/viewcvs.cgi/MITgcm_contrib/quarter_degree_global/input/data.exf?rev=HEAD&content-type=text/vnd.viewcvs-markup
to see a sample of the data.exf for the interpolation routine.

You'll also need to define USE_EXF_INTERPOLATION, in ECCO_CPPOPTIONS

Matt


Ming Guo wrote:

> Hi, Matt,
>
> As I am using uniform time-dependent wind stress, how to generate the 
> stress file? just create ustressfile like, ustre(t1), ustre(t2)... and 
> the model can give ustress value to all the grids,  or I also need to 
> specify the value of every grids as gendata.m in exp0?
>
> thanks
> Ming
>
>
> On Wed, 7 Sep 2005, Matthew Mazloff wrote:
>
>> Hi Ming,
>>
>> I am a bit surprised; I just looked at the EXF & MNC package and I 
>> don't the model is able to read in NetCDF format input files.  Maybe 
>> someone in the know can tell us what the status is of using NetCDF 
>> input. Anyway, I know the model can read in binary input files and 
>> the precision is given by exf_iprec = 32 (or 64).  I actually sent an 
>> email under the thread name "Starting with MITgcm" that was about 
>> generating input files a few weeks ago which I'll append below.  You 
>> should easily be able to tell if the forcing fields are being read in 
>> correctly.   Check the monitor statistics for your forcing fields and 
>> see if they seem reasonable.  Also, if the model crashes because it 
>> cannot find an input file, it should give an error message that 
>> includes the name of the file it last looked for.  Remember that if 
>> you give the input file name exf_input.data and the model can't find 
>> this file it may append a ".data" on it and try again.  So if the 
>> error says it can't find exf_input.data.data that's why. And just in 
>> case you were referring to the previous issue of array precision, 
>> I'll add that exf_yftype refers to the precision with which the exf 
>> package should read arrays.  Your choices are RL for REAL*8 or RS for 
>> REAL*4. once again hoping I'm giving accurate info,
>> Matt
>>
>>
>> Here's the old email:
>>
>> Hi Matej,
>>
>> As Ed said, the verification experiments have matlab scripts that 
>> describe preperation of input files. For example, in MITgcm / 
>> verification / exp5 / input / gendata.m
>> a surface forcing file is made:
>>
>> Q=Qo*(1+0.01*rand([nx,ny]));
>>
>> it is size [nx,ny]
>> if it were 3-d (e.g. and initial theta file) it would be size [nx,ny,nz]
>>
>> then it is written with
>>
>> fid=fopen('Qnet.circle','w','b');
>> fwrite(fid,Q,'real*8');
>> fclose(fid);
>>
>> The data is written by fwrite down the matrix columns.
>>
>> it is written translated into real*8 because the mitgcm data file 
>> given in the verification experiment has
>> readBinaryPrec=64,
>>
>> it is read in as a surface heating file by putting
>> # Input datasets
>> &PARM05
>> surfQfile='Qnet.circle',
>> &
>> in the data file
>> other possible initial files you can give the model are (as seen in  
>> MITgcm / model / src / ini_parms.F )
>> C--   Input files
>>    NAMELIST /PARM05/
>>   & bathyFile, topoFile,
>>   & hydrogThetaFile, hydrogSaltFile,
>>   & zonalWindFile, meridWindFile,
>>   & thetaClimFile, saltClimFile,
>>   & surfQfile, surfQnetFile, surfQswFile, EmPmRfile, saltFluxFile,
>>   & lambdaThetaFile, lambdaSaltFile,
>>   & uVelInitFile, vVelInitFile, pSurfInitFile,
>>   & dQdTFile, ploadFile,tCylIn,tCylOut,
>>   & eddyTauxFile, eddyTauyFile,
>>   & mdsioLocalDir,
>>   & the_run_name
>> CEOP
>>
>>
>>
>> -matt
>>
>>
>>
>> Ming Guo wrote:
>>
>>> Hi, Matt,
>>>
>>> just wonder the format of the focing files, such as ustress and 
>>> vstress, should be NetCDF file, or something else?
>>>
>>> thanks,
>>> Ming
>>>
>>>
>>> On Mon, 5 Sep 2005, Matthew Mazloff wrote:
>>>
>>>> Hi Ming,
>>>>
>>>> The problem is
>>>>
>>>> yftype_exf='RL',
>>>>
>>>> in data.exf
>>>>
>>>> I looked in MITgcm/pkg /exf/exf_readparms.F
>>>> and found
>>>> exf_yftype but not yftype_exf.
>>>>
>>>> You should switch this.
>>>>
>>>> -Matt
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Ming Guo wrote:
>>>>
>>>>> Hi, Ed,
>>>>> I just set the files, but the errors still there,
>>>>>
>>>>> "
>>>>> namelist read: variable not in namelist
>>>>> apparent state: unit 11 named /tmp/tmp.FA6VrWo
>>>>> last formate: list io
>>>>> latey reading sequential formatted external IO
>>>>> Abort (core dumped)
>>>>> "
>>>>>
>>>>> The attachments are my "EXF" files.
>>>>> Can you help me to find out the problem?
>>>>> By the way, is there any spectial format needed for the force file?
>>>>>
>>>>> thanks,
>>>>> Ming
>>>>>
>>>>>
>>>>>
>>>>
>>>> _______________________________________________
>>>> MITgcm-support mailing list
>>>> MITgcm-support at mitgcm.org
>>>> http://mitgcm.org/mailman/listinfo/mitgcm-support
>>>>
>>> _______________________________________________
>>> MITgcm-support mailing list
>>> MITgcm-support at mitgcm.org
>>> http://mitgcm.org/mailman/listinfo/mitgcm-support
>>
>>
>>
> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mitgcm.org/mailman/listinfo/mitgcm-support