[Met_help] Input data for point-stat tool

[capecchi]

John,
thanks very much for your help, I decided to convert my NetCDF file to GRIB1
file
using `cdo -f grb copy ...` command...do you have any (...) about known
problems with this
procedure?
Anyway I hope version 2.0 of MET will accept general format of NetCDF files.
Thanks again, bye, Valerio

2008/9/23 John Halley Gotway <johnhg at rap.ucar.edu>

> Valerio,
>
> I do think that it would be reasonable to massage your NetCDF files into a
> format that METv1.1 would read.  However, METv1.1 is only compatible with a
> rather rigid format of NetCDF at this point.  For
> the next release of MET, version 2.0, we're planning to support a more
> general format of NetCDF.
>
> Currently, MET expects gridded NetCDF data to abide by the following
> conventions:
>
> (1) dimensions named "lat" and "lon" define the dimension of the data.
> (2) variables have only two dimensions, "lat" and "lon".
> (3) variables are named using the GRIB code abbreviation for the GRIB field
> they represent and are in the units prescribed by that GRIB code.  For
> example, a variable containing accumulated
> precipitation would be named "APCP" (GRIB code abbreviation) and its units
> would be millimeters.
> (4) several variable attributes are required to define the initialization,
> valid, and accumulation (if applicable) times.
> (5) global attributes defining the grid on which the data resides must be
> defined.
>
> The definition of the grid in (5) is necessary to perform conversions
> between lat/lon and grid x/y.
>
> I've attached a sample output file from PCP-Combine.  This example contains
> data on a lat/lon grid - which I'm guessing is the projection your data is
> on.  The attached file that ends in ".dump" is
> just a dump of the NetCDF header.  In that file, please note the following:
>
> (1) The "lat" and "lon" dimensions are defined.
> (2) The variable named APCP contains accumulated precipitation in mm.  The
> GRIB codes and corresponding abbreviations are defined here:
> http://www.nco.ncep.noaa.gov/pmb/docs/on388/table2.html
> (3) The APCP variable contains the several attributes, but only the
> following are actually read by the code: level, init_time_ut, valid_time_ut,
> and accum_time (if not applicable, just set to 0).
> The "_ut" is for unixtime, or seconds since January 1, 1970.
> (4) Global attributes defining the projectsion:
> :Projection = "LatLon" ;
> :lat_ll_deg = "25.063000 degrees_north" ;
> :lon_ll_deg = "-124.938000 degrees_east" ;
> :delta_lat_deg = "0.125000 degrees" ;
> :delta_lon_deg = "0.125000 degrees" ;
> :Nlat = "224 grid_points" ;
> :Nlon = "464 grid_points" ;
> Here you'll just insert your grid definition info.
>
> Hope that helps, and feel free to write with more questions about this.
>
> John Halley-Gotway
> johnhg at ucar.edu
>
>
> capecchi wrote:
> > Dear met_help,
> > I'm currently involved in WRF verification issues for a biometeorological
> > service in Italy.
> > I'm interested in point-stat tools but I have, as input forecast data,
> > NetCDF files derived and post-elaborated from WRF GRIB1 output.
> > I read from MET User Guide that I'm supposed to provide as input data
> only
> > GRIB1 files or NetCDF format
> > that is output from the Pcp-Combine tool; I'm wondering if my NetCDF file
> > format are like the Pcp-Combine tool's format
> > (I'm attaching one as sample) or if you can suggest me some NetCDF to
> GRIB1
> > converter tools (like cdo, nco, or...)
> > Thanks in advance for any help you can give me, regards, Valerio Capecchi
> >
> >
> **************************************************************************
> >
> > Valerio Capecchi
> >
> >
> --------------------------------------------------------------------------
> > Interdepartemental Centre of Bioclimatology - University of Florence
> > Piazzale delle Cascine 18
> > 50144 Firenze. Italia
> > Tel: +39 0553288257
> > Fax: +39 055332472
> >
> > WEB http://www.unifi.it/cib
> >
> ---------------------------------------------------------------------------
> > CNR IBIMET - LaMMA (Laboratory for Meteorology and Environmental
> Modelling)
> > EDIFICIO D
> > VIA MADONNA DEL PIANO           50019 SESTO FIORENTINO (FI)
> > tel  +39 055  5226041/2
> > fax  +39 055  444083
> >
> > http://www.lamma.rete.toscana.it/bioclima
> >
> ---------------------------------------------------------------------------
> >
> >
> ***************************************************************************
> >
> >
> >
> > ------------------------------------------------------------------------
> >
> > _______________________________________________
> > Met_help mailing list
> > Met_help at mailman.ucar.edu
> > http://mailman.ucar.edu/mailman/listinfo/met_help
>
> netcdf nam.20070330.ncep110 {
> dimensions:
>        lat = 224 ;
>        lon = 464 ;
> variables:
>        float lat(lat, lon) ;
>                lat:units = "degrees_north" ;
>                lat:long_name = "Latitude" ;
>                lat:_FillValue = -9999.f ;
>        float lon(lat, lon) ;
>                lon:units = "degrees_east" ;
>                lon:long_name = "Longitude" ;
>                lon:_FillValue = -9999.f ;
>        float APCP(lat, lon) ;
>                APCP:grib_code = 61 ;
>                APCP:units = "kg/m^2" ;
>                APCP:long_name = "Total precipitation" ;
>                APCP:level = "SFC" ;
>                APCP:_FillValue = -9999.f ;
>                APCP:init_time = "20070330_000000" ;
>                APCP:init_time_ut = 1175212800 ;
>                APCP:valid_time = "20070331_120000" ;
>                APCP:valid_time_ut = 1175342400 ;
>                APCP:accum_time = "6 hours" ;
>
> // global attributes:
>                :FileOrigins = "File /home/johnhg/nam.20070330.ncep110.ncgenerated 20080923_163157 UTC on host billiken by the PCP-Combine tool" ;
>                :RunCommand = "Addition:
> /home/johnhg/nam.20070330.ncep110.grb with accumulation of 3 hours plus
> /home/johnhg/nam.20070330.ncep110.grb with accumulation of 3 hours." ;
>                :Projection = "LatLon" ;
>                :lat_ll_deg = "25.063000 degrees_north" ;
>                :lon_ll_deg = "-124.938000 degrees_east" ;
>                :delta_lat_deg = "0.125000 degrees" ;
>                :delta_lon_deg = "0.125000 degrees" ;
>                :Nlat = "224 grid_points" ;
>                :Nlon = "464 grid_points" ;
> }
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/met_help/attachments/20080925/84836dd0/attachment.html