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Convert grb2 to grb1

Added by Alessio Spassiani almost 11 years ago

Hi,

I am trying to convert CFSR grib2 data downloaded from the NOMADS website to grib1 format using the CDO operator 'copy'.
The command I use is as follows:

cdo -f grb copy pgbhnl.gdas.$year$month$day$hour.grb2 cfsr.$year$month$day$hour.grb

however I get the following error:

cdo copy: Open failed on >pgbhnl.gdas.2008070418.grb2<
Unsupported file structure

I have used this operator successful with CFSv2 data which is also in grib2.

The data files I am having issues with are too large to attach but one can be downloaded from the link below.
http://nomads.ncdc.noaa.gov/modeldata/cmd_pgbh/2008/200807/20080704/pgbhnl.gdas.2008070418.grb2

Any help would be greatly appreciated, even if there is another alternative to convert these file from grib2 to grib1.

Thank you in advance,
Alessio


Replies (4)

RE: Convert grb2 to grb1 - Added by Ralf Mueller almost 11 years ago

I get the same error with 

m@thingol:~/Downloads]cdo -V                                                               [22:22:49|14-05-05]
Climate Data Operators version 1.6.3 (http://code.zmaw.de/projects/cdo)
Compiled: by ram on thingol (x86_64-unknown-linux-gnu) Mar  3 2014 13:49:07
Compiler: gcc -g -O3 -std=gnu99 -Wall -fopenmp -march=native  
 version: gcc (GCC) 4.8.2 20140206 (prerelease)
Features: PTHREADS OpenMP NC4 OPeNDAP SZ Z UDUNITS2
Libraries:
Filetypes: srv ext ieg grb grb2 nc nc2 nc4 nc4c 
     CDI library version : 1.6.3 of Mar  3 2014 13:48:52
 CGRIBEX library version : 1.6.3 of Jan  8 2014 19:55:18
GRIB_API library version : 1.10.0
  netCDF library version : 4.3.1.1 of Mar 12 2014 13:06:59 $
    HDF5 library version : 1.8.11
 SERVICE library version : 1.3.1 of Mar  3 2014 13:48:47
   EXTRA library version : 1.3.1 of Mar  3 2014 13:48:46
     IEG library version : 1.3.1 of Mar  3 2014 13:48:46
    FILE library version : 1.8.2 of Mar  3 2014 13:48:46

I also tried ncl_convert2nc from the ncl package. It prints some errors like 

Is the JPEG2000 driver available?dec_jpeg2000: Unable to open JPEG2000 image within GRIB file.
ERROR 4: `/vsimem/work415.jpc' not recognised as a supported file format.
but creates a results netcdf file. Might help.
BTW, I'm not sure, if every grib2 file can be converted to grib1.

regards
ralf

RE: Convert grb2 to grb1 - Added by Ralf Mueller almost 11 years ago

here is the resulting file structure

[ram@thingol:~/Downloads]cdo sinfov pgbhnl.gdas.2008070418.nc                                 [22:31:27|14-05-05]
   File format: netCDF
    -1 : Institut Source   Ttype    Levels Num  Gridsize Num Dtype : Parameter name
     1 : unknown  unknown  constant      1   1    259920   1  F32  : TMP_P0_L6_GLL0
     2 : unknown  unknown  constant      1   1    259920   1  F32  : TMP_P0_L7_GLL0
     3 : unknown  unknown  constant     37   2    259920   1  F32  : TMP_P0_L100_GLL0
     4 : unknown  unknown  constant      4   3    259920   1  F32  : TMP_P0_L102_GLL0
     5 : unknown  unknown  constant      1   1    259920   1  F32  : TMP_P0_L104_GLL0
     6 : unknown  unknown  constant      1   1    259920   1  F32  : TMP_P0_2L108_GLL0
     7 : unknown  unknown  constant      2   4    259920   1  F32  : TMP_P0_L109_GLL0
     8 : unknown  unknown  constant      1   1    259920   1  F32  : POT_P0_L104_GLL0
     9 : unknown  unknown  constant      1   1    259920   1  F32  : DPT_P0_2L108_GLL0
    10 : unknown  unknown  constant     37   2    259920   1  F32  : SPFH_P0_L100_GLL0
    11 : unknown  unknown  constant      1   1    259920   1  F32  : SPFH_P0_2L108_GLL0
    12 : unknown  unknown  constant      1   1    259920   1  F32  : RH_P0_L4_GLL0 
    13 : unknown  unknown  constant     37   2    259920   1  F32  : RH_P0_L100_GLL0
    14 : unknown  unknown  constant      4   5    259920   1  F32  : RH_P0_2L104_GLL0
    15 : unknown  unknown  constant      1   1    259920   1  F32  : RH_P0_L104_GLL0
    16 : unknown  unknown  constant      1   1    259920   1  F32  : RH_P0_2L108_GLL0
    17 : unknown  unknown  constant      1   1    259920   1  F32  : RH_P0_L200_GLL0
    18 : unknown  unknown  constant      1   1    259920   1  F32  : RH_P0_L204_GLL0
    19 : unknown  unknown  constant      1   1    259920   1  F32  : PWAT_P0_2L108_GLL0
    20 : unknown  unknown  constant      1   1    259920   1  F32  : PWAT_P0_L200_GLL0
    21 : unknown  unknown  constant     32   6    259920   1  F32  : CLWMR_P0_L100_GLL0
    22 : unknown  unknown  constant      1   1    259920   1  F32  : UGRD_P0_L6_GLL0
    23 : unknown  unknown  constant      1   1    259920   1  F32  : UGRD_P0_L7_GLL0
    24 : unknown  unknown  constant     37   2    259920   1  F32  : UGRD_P0_L100_GLL0
    25 : unknown  unknown  constant      4   3    259920   1  F32  : UGRD_P0_L102_GLL0
    26 : unknown  unknown  constant      1   1    259920   1  F32  : UGRD_P0_L104_GLL0
    27 : unknown  unknown  constant      1   1    259920   1  F32  : UGRD_P0_2L108_GLL0
    28 : unknown  unknown  constant      2   4    259920   1  F32  : UGRD_P0_L109_GLL0
    29 : unknown  unknown  constant      1   1    259920   1  F32  : VGRD_P0_L6_GLL0
    30 : unknown  unknown  constant      1   1    259920   1  F32  : VGRD_P0_L7_GLL0
    31 : unknown  unknown  constant     37   2    259920   1  F32  : VGRD_P0_L100_GLL0
    32 : unknown  unknown  constant      4   3    259920   1  F32  : VGRD_P0_L102_GLL0
    33 : unknown  unknown  constant      1   1    259920   1  F32  : VGRD_P0_L104_GLL0
    34 : unknown  unknown  constant      1   1    259920   1  F32  : VGRD_P0_2L108_GLL0
    35 : unknown  unknown  constant      2   4    259920   1  F32  : VGRD_P0_L109_GLL0
    36 : unknown  unknown  constant     37   2    259920   1  F32  : STRM_P0_L100_GLL0
    37 : unknown  unknown  constant     37   2    259920   1  F32  : VPOT_P0_L100_GLL0
    38 : unknown  unknown  constant     37   2    259920   1  F32  : VVEL_P0_L100_GLL0
    39 : unknown  unknown  constant      1   1    259920   1  F32  : VVEL_P0_L104_GLL0
    40 : unknown  unknown  constant     37   2    259920   1  F32  : ABSV_P0_L100_GLL0
    41 : unknown  unknown  constant      1   1    259920   1  F32  : VWSH_P0_L7_GLL0
    42 : unknown  unknown  constant      2   4    259920   1  F32  : VWSH_P0_L109_GLL0
    43 : unknown  unknown  constant      1   1    259920   1  F32  : USTM_P0_2L103_GLL0
    44 : unknown  unknown  constant      1   1    259920   1  F32  : VSTM_P0_2L103_GLL0
    45 : unknown  unknown  constant      1   1    259920   1  F32  : PRES_P0_L1_GLL0
    46 : unknown  unknown  constant      1   1    259920   1  F32  : PRES_P0_L6_GLL0
    47 : unknown  unknown  constant      1   1    259920   1  F32  : PRES_P0_L7_GLL0
    48 : unknown  unknown  constant      1   1    259920   1  F32  : PRES_P0_L101_GLL0
    49 : unknown  unknown  constant      2   4    259920   1  F32  : PRES_P0_L109_GLL0
    50 : unknown  unknown  constant      1   1    259920   1  F32  : PRMSL_P0_L101_GLL0
    51 : unknown  unknown  constant      1   1    259920   1  F32  : HGT_P0_L1_GLL0
    52 : unknown  unknown  constant      1   1    259920   1  F32  : HGT_P0_L4_GLL0
    53 : unknown  unknown  constant      1   1    259920   1  F32  : HGT_P0_L6_GLL0
    54 : unknown  unknown  constant      1   1    259920   1  F32  : HGT_P0_L7_GLL0
    55 : unknown  unknown  constant     37   2    259920   1  F32  : HGT_P0_L100_GLL0
    56 : unknown  unknown  constant      2   4    259920   1  F32  : HGT_P0_L109_GLL0
    57 : unknown  unknown  constant      1   1    259920   1  F32  : HGT_P0_L204_GLL0
    58 : unknown  unknown  constant      2   7    259920   1  F32  : GPA_P0_L100_GLL0
    59 : unknown  unknown  constant      1   1    259920   1  F32  : 5WAVH_P0_L100_GLL0
    60 : unknown  unknown  constant      1   1    259920   1  F32  : 5WAVA_P0_L100_GLL0
    61 : unknown  unknown  constant      1   1    259920   1  F32  : CWAT_P0_L200_GLL0
    62 : unknown  unknown  constant      1   1    259920   1  F32  : PLI_P0_2L108_GLL0
    63 : unknown  unknown  constant      1   1    259920   1  F32  : CAPE_P0_L1_GLL0
    64 : unknown  unknown  constant      3   8    259920   1  F32  : CAPE_P0_2L108_GLL0
    65 : unknown  unknown  constant      1   1    259920   1  F32  : CIN_P0_L1_GLL0
    66 : unknown  unknown  constant      3   8    259920   1  F32  : CIN_P0_2L108_GLL0
    67 : unknown  unknown  constant      2   9    259920   1  F32  : HLCY_P0_2L103_GLL0
    68 : unknown  unknown  constant      1   1    259920   1  F32  : LFTX_P0_L1_GLL0
    69 : unknown  unknown  constant      1   1    259920   1  F32  : 4LFTX_P0_L1_GLL0
    70 : unknown  unknown  constant      1   1    259920   1  F32  : TOZNE_P0_L200_GLL0
    71 : unknown  unknown  constant     37   2    259920   1  F32  : O3MR_P0_L100_GLL0
    72 : unknown  unknown  constant      1   1         2   2  F32  : lv_HTGL7_l1   
    73 : unknown  unknown  constant      1   1         2   2  F32  : lv_HTGL7_l0   
    74 : unknown  unknown  constant      1   1         3   3  F32  : lv_SPDL6_l1   
    75 : unknown  unknown  constant      1   1         3   3  F32  : lv_SPDL6_l0   
    76 : unknown  unknown  constant      1   1         4   4  F32  : lv_SIGL3_l1   
    77 : unknown  unknown  constant      1   1         4   4  F32  : lv_SIGL3_l0   
   Grid coordinates :
     1 : lonlat       > size      : dim = 259920  nx = 720  ny = 361
                        lon_0     : first = 0  last = 359.5  inc = 0.5  degrees_east  circular
                        lat_0     : first = 90  last = -90  inc = -0.5  degrees_north
     2 : generic      > size      : dim = 2  nx = 2  ny = 0
     3 : generic      > size      : dim = 3  nx = 3  ny = 0
     4 : generic      > size      : dim = 4  nx = 4  ny = 0
   Vertical coordinates :
     1 : surface                  : 0 
     2 : pressure              Pa : 100 200 300 500 700 1000 2000 3000 5000 7000 10000 
                                    12500 15000 17500 20000 22500 25000 30000 35000 
                                    40000 45000 50000 55000 60000 65000 70000 75000 
                                    77500 80000 82500 85000 87500 90000 92500 95000 
                                    97500 100000 
     3 : generic                m : 1829 2743 3658 4572 
     4 : generic            K m2 kg-1 s- : -1.99999999e-06 1.99999999e-06 
     5 : generic            level : 1 2 3 4 
     6 : pressure              Pa : 1000 2000 3000 5000 7000 10000 12500 15000 17500 
                                    20000 22500 25000 30000 35000 40000 45000 50000 
                                    55000 60000 65000 70000 75000 77500 80000 82500 
                                    85000 87500 90000 92500 95000 97500 100000 
     7 : pressure              Pa : 50000 100000 
     8 : generic            level : 1 2 3 
     9 : generic            level : 1 2 
cdo sinfon: Processed 77 variables ( 0.00s )

RE: Convert grb2 to grb1 - Added by Alessio Spassiani almost 11 years ago

Thanks for the response Ralf.

I ended up downloading the CFSR data from CISL Research Data Archive which doesn't give me the error I was getting before.

I however noticed that when I do change the format from grib2 to grib1 certain variables aren't carried over and new ones are created in the process.

This is the control file for the data originally in grib2.

dset ^./cfsr.%y4%m2%d2.grb2
index ^./cfsr.20080703.grb2.idx
undef 9.999E+20
title ./cfsr.20080703.grb2
* produced by g2ctl v0.0.8.8
* command line options: -0 ./cfsr.%y4%m2%d2.grb2
* griddef=1:0:(720 x 361):grid_template=0:winds(N/S): lat-lon grid:(720 x 361) units 1e-06 input WE:NS output WE:SN res 48 lat 90.000000 to -90.000000 by 0.500000 lon 0.000000 to 359.500000 by 0.500000 #points=259920:winds(N/S)

dtype grib2
options template
ydef 361 linear -90.000000 0.5
xdef 720 linear 0.000000 0.500000
tdef 3449 linear 00Z03jul2008 6hr
* PROFILE hPa
zdef 37 levels 100000 97500 95000 92500 90000 87500 85000 82500 80000 77500 75000 70000 65000 60000 55000 50000 45000 40000 35000 30000 25000 22500 20000 17500 15000 12500 10000 7000 5000 3000 2000 1000 700 500 300 200 100
options pascals
vars 6
HGTprs    37,100  0,3,5 ** (1000 975 950 925 900.. 7 5 3 2 1) Geopotential Height [gpm]
PRESmsl   0,101,0   0,3,0 ** mean sea level Pressure [Pa]
PRMSLmsl   0,101,0   0,3,1 ** mean sea level Pressure Reduced to MSL [Pa]
TMPprs    37,100  0,0,0 ** (1000 975 950 925 900.. 7 5 3 2 1) Temperature [K]
UGRDprs    37,100  0,2,2 ** (1000 975 950 925 900.. 7 5 3 2 1) U-Component of Wind [m/s]
VGRDprs    37,100  0,2,3 ** (1000 975 950 925 900.. 7 5 3 2 1) V-Component of Wind [m/s]
ENDVARS

And here is the control file after converting to grib1.

dset ^./cfsr.%y4%m2%d2.grb
index ^./cfsr.20080703.grb.idx
undef 9.999E+20
title ./cfsr.20080703.grb
*  produced by grib2ctl v0.9.12.6
dtype grib 255
options template
options yrev
ydef 361 linear -90.000000 0.5
xdef 720 linear 0.000000 0.500000
tdef 3449 linear 00Z03jul2008 6hr
*  z has 37 levels, for prs
zdef 37 levels
1000 975 950 925 900 875 850 825 800 775 750 700 650 600 550 500 450 400 350 300 250 225 200 175 150 125 100 70 50 30 20 10 7 5 3 2 1
vars 5
ICAHTprs 37 5,100,0 ** (profile) ICAO Standard Atmosphere Reference Height [M]
PRESmsl  0 1,102,0 ** mean-sea level Pressure [Pa]
PRMSLprs 37 2,100,0 ** (profile) Pressure reduced to MSL [Pa]
var0prs 37 0,100,0 ** (profile) undefined
var0msl  0 0,102,0 ** mean-sea level undefined
ENDVARS

Do you have any thoughts as to why that is.

Thanks for the help,
Alessio

Download all files
cfsr_08_10.ctl (1.25 KB) cfsr_08_10.ctl Control file of the data in grib2
cfsr_08_10_grb.ctl (751 Bytes) cfsr_08_10_grb.ctl Control file of the data converted to grib1

RE: Convert grb2 to grb1 - Added by Ralf Mueller almost 11 years ago

As I said: grib2 is a developing standard,so there will be variables defined in grib2 but not in grib1. See this note from grib homepage.

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