[Met_help] [rt.rap.ucar.edu #88472] History for Question on how to use climatology in grid_stat

[John Halley Gotway via RT]

----------------------------------------------------------------
  Initial Request
----------------------------------------------------------------

Hello MET support,

I am with the Global Modeling and Assimilation Office (GMAO) at NASA. We are interested in using MET for some verification metrics in GEOS5 model development. Therefore, we have begun experimenting with the MET software package. Currently, I have encountered a problem using grid_stat, whereby the error message is:

WARNING: read_climo_file() -> Trouble reading climatology file "/discover/nobackup/projects/gmao/g6dev/sdrabenh/validation_data/merra2/MERRA2.monthly.198001-201706.var-T.nc4"

The grid_stat executable completes but ignores using a climatology. The basic setup is the forecast (version of GEOS5), observation (ECMWF interim), and climatology (MERRA2) are all gridded netcdf files. The MERRA2 climatology already has a precomputed monthly mean (and std dev if necessary) so NO time averaging is needed. My intent was for grid-stat to read the specified climatological mean variable and level just as is. However, I cannot seem to get grid_stat to do this. Is this possible? If so, how should I change my configuration options? Please see snippets from my config file below. I look forward to any help you could provide.

Thanks,
Scott Rabenhorst



My config ----------------------------------------------------

fcst = {
   file_type = NETCDF_NCCF;
   field = [ { name = "T"; level = "(0,0,*,*)"; } ];
}

obs = {
   file_type = NETCDF_NCCF;
   field = [ { name = "t"; level = "(264,36,*,*)"; } ];
}

climo_mean = {
   file_name = "/discover/nobackup/projects/gmao/g6dev/sdrabenh/validation_data/merra2/MERRA2.monthly.198001-201706.var-T.nc4" ;
   field = [
      {
        name       = "T";
        level      = "(252,0,*,*)" ;
      }
   ];

   regrid = {
      method     = NEAREST;
      width      = 1;
      vld_thresh = 0.5;
      shape      = SQUARE;
   }

   time_interp_method = NONE;
   match_month        = FALSE;
   match_day          = FALSE;
   time_step          = 2678400;
}

climo_stdev = climo_mean;
climo_stdev = {
   file_name = [];
}

climo_cdf_bins = 1;


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  Complete Ticket History
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Subject: Question on how to use climatology in grid_stat
From: John Halley Gotway
Time: Fri Jan 11 14:43:30 2019

Hi Scott,

I see you have a question about getting Grid-Stat to read MERRA2
climatological data.  I went hunting around on the GES DISC website
and
found info about MERRA2, but wasn't able to locate the exact file you
referenced.

However, looking in the config file info you sent, I see that in the
forecast and observation dictionaries, you've used the "file_type =
NETCDF_NCCF;" option tell MET to interpret that NetCDF data as being
CF-compliant.  I'd suggest adding the same option to the climo
dictionary:


*climo_mean = {    file_name = "/discover/nobackup/projects/g*
*mao/g6dev/sdrabenh/validation_**data/merra2/MERRA2.monthly.*

*198001-201706.var-T.nc4" ;    field = [       {*

*         file_type = NETCDF_NCCF;*

*        name       = "T";         level      = "(252,0,*,*)" ;*

*       }    ];*

If that doesn't do the trick, please send me that MERRA2 data file so
I can
do some more testing.

Another suggestion... the MET config files support the use of
environment
variables.  So when scripting up calls to Grid-Stat, you may find it
convenient to define the "level" info as an environment variable and
have
the calling script set that.

Please let me know how it goes.

Thanks,
John Halley Gotway

On Thu, Jan 10, 2019 at 8:27 AM Rabenhorst, Scott D. (GSFC-
610.1)[SCIENCE
SYSTEMS AND APPLICATIONS INC] via RT <met_help at ucar.edu> wrote:

>
> Thu Jan 10 08:27:42 2019: Request 88472 was acted upon.
> Transaction: Ticket created by scott.d.rabenhorst at nasa.gov
>        Queue: met_help
>      Subject: Question on how to use climatology in grid_stat
>        Owner: Nobody
>   Requestors: scott.d.rabenhorst at nasa.gov
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=88472 >
>
>
> Hello MET support,
>
> I am with the Global Modeling and Assimilation Office (GMAO) at
NASA. We
> are interested in using MET for some verification metrics in GEOS5
model
> development. Therefore, we have begun experimenting with the MET
software
> package. Currently, I have encountered a problem using grid_stat,
whereby
> the error message is:
>
> WARNING: read_climo_file() -> Trouble reading climatology file
>
"/discover/nobackup/projects/gmao/g6dev/sdrabenh/validation_data/merra2/MERRA2.monthly.198001-
201706.var-T.nc4"
>
> The grid_stat executable completes but ignores using a climatology.
The
> basic setup is the forecast (version of GEOS5), observation (ECMWF
> interim), and climatology (MERRA2) are all gridded netcdf files. The
MERRA2
> climatology already has a precomputed monthly mean (and std dev if
> necessary) so NO time averaging is needed. My intent was for grid-
stat to
> read the specified climatological mean variable and level just as
is.
> However, I cannot seem to get grid_stat to do this. Is this
possible? If
> so, how should I change my configuration options? Please see
snippets from
> my config file below. I look forward to any help you could provide.
>
> Thanks,
> Scott Rabenhorst
>
>
>
> My config ----------------------------------------------------
>
> fcst = {
>    file_type = NETCDF_NCCF;
>    field = [ { name = "T"; level = "(0,0,*,*)"; } ];
> }
>
> obs = {
>    file_type = NETCDF_NCCF;
>    field = [ { name = "t"; level = "(264,36,*,*)"; } ];
> }
>
> climo_mean = {
>    file_name =
>
"/discover/nobackup/projects/gmao/g6dev/sdrabenh/validation_data/merra2/MERRA2.monthly.198001-
201706.var-T.nc4"
> ;
>    field = [
>       {
>         name       = "T";
>         level      = "(252,0,*,*)" ;
>       }
>    ];
>
>    regrid = {
>       method     = NEAREST;
>       width      = 1;
>       vld_thresh = 0.5;
>       shape      = SQUARE;
>    }
>
>    time_interp_method = NONE;
>    match_month        = FALSE;
>    match_day          = FALSE;
>    time_step          = 2678400;
> }
>
> climo_stdev = climo_mean;
> climo_stdev = {
>    file_name = [];
> }
>
> climo_cdf_bins = 1;
>
>

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