Re: [ferret_users] Keeping NetCDF dimension attributes on a subregion

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi Paulo,
>From the NOTE in the session you quote, I see that you are using Ferret version 6.  In that version the command

set attribute/output=all varname

should tell Ferret to write all of the attributes.  In this case we want the attributes of coordinate variables, so the syntax is to put the name of the coordinate variable in parentheses.

use air.2m.gauss.1998.nc
set reg/x=-25:-1/y=10:50
set att/output=all (`air,return=xaxis`)
set att/output=all (`air,return=yaxis`)
set att/output=all (`air,return=zaxis`)
set att/output=all (`air,return=taxis`)
set att/output=all air
save/file=sset.cdf/clobber air

In addition , you can have Ferret write everything in its initial upper- or lower-case form, if you like.  Before the SAVE statement, put

CANCEL MODE upcase

Paulo B. Oliveira wrote:

Hello All, 

I'm trying to create a regional subset of NCEP2 data
(ftp://ftp.cdc.noaa.gov/Datasets/ncep.reanalysis2) but the dimension
attributes get lost. Is there a simple way to do this ?

Thanks.


Paulo.
-----------
Ferret cmds:

use air.2m.gauss.1998.nc
set reg/x=-25:-1/y=10:50
save/file=sset.cdf/clobber air
 LISTing to file sset.cdf
 *** NOTE: Converting data type of missing_value NC_SHORT to match
output type of variable NC_FLOAT


NetCDF files:

================================ OUTPUT ================================
OUTPUT: -- dim and var attrib. lost.
$ ncdump -h sset.cdf
netcdf sset {
dimensions:
        LONN12_0 = 13 ;
        LAT53_74 = 22 ;
        bnds = 2 ;
        LEVEL = 1 ;
        TIME = UNLIMITED ; // (1460 currently)
variables:
        double LONN12_0(LONN12_0) ;
        double LAT53_74(LAT53_74) ;
        double LAT53_74_bnds(LAT53_74, bnds) ;
        double LEVEL(LEVEL) ;
        double TIME(TIME) ;
        float AIR(TIME, LEVEL, LAT53_74, LONN12_0) ;
                AIR:missing_value = 775.31f ;
                AIR:_FillValue = 775.31f ;
                AIR:long_name = "6-Hourly Forecast of Air temperature at
2 m" ;
                AIR:units = "degK" ;
                AIR:history = "From air.2m.gauss.1998" ;

================================ INPUT ================================
$ ncdump -h air.2m.gauss.1998.nc
netcdf air.2m.gauss.1998 {
dimensions:
        lon = 192 ;
        lat = 94 ;
        level = 1 ;
        time = UNLIMITED ; // (1460 currently)
variables:
        float level(level) ;
                level:units = "m" ;
                level:actual_range = 2.f, 2.f ;
                level:long_name = "Level" ;
                level:positive = "up" ;
                level:axis = "z" ;
                level:coordinate_defines = "point" ;
        float lat(lat) ;
                lat:units = "degrees_north" ;
                lat:actual_range = 88.542f, -88.542f ;
                lat:long_name = "Latitude" ;
                lat:standard_name = "latitude_north" ;
                lat:axis = "y" ;
                lat:coordinate_defines = "point" ;
        float lon(lon) ;
                lon:units = "degrees_east" ;
                lon:long_name = "Longitude" ;
                lon:actual_range = 0.f, 358.125f ;
                lon:standard_name = "longitude_east" ;
                lon:axis = "x" ;
                lon:coordinate_defines = "point" ;
        double time(time) ;
                time:units = "hours since 1800-1-1 00:00:0.0" ;
                time:long_name = "Time" ;
                time:actual_range = 1735632., 1744386. ;
                time:delta_t = "0000-00-00 06:00:00" ;
                time:standard_name = "time" ;
                time:axis = "t" ;
                time:coordinate_defines = "point" ;
        short air(time, level, lat, lon) ;
                air:long_name = "6-Hourly Forecast of Air temperature at
2 m" ;
                air:valid_range = -32765s, -1765s ;
                air:unpacked_valid_range = 120.f, 430.f ;
                air:actual_range = 182.59f, 327.68f ;
                air:units = "degK" ;
                air:add_offset = 447.65f ;
                air:scale_factor = 0.01f ;
                air:missing_value = 32766s ;
                air:_FillValue = -32767s ;
                air:precision = 2s ;
                air:least_significant_digit = 1s ;
                air:GRIB_id = 11s ;
                air:GRIB_name = "TMP" ;
                air:var_desc = "Air temperature" ;
                air:dataset = "NCEP/DOE AMIP-II Reanalysis
(Reanalysis-2)" ;
                air:level_desc = "2 m" ;
                air:statistic = "Mean" ;
                air:parent_stat = "Individual Obs" ;
                air:standard_name = "air_temperature" ;


  

-- 

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Ansley Manke, NOAA/PMEL   ansley.b.manke@xxxxxxxx
7600 Sand Point Way NE, Seattle WA
Phone 206-526-6246,  FAX 206-526-6744