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Re: New Ticket - [netCDFDecoders !FEG-733021]: Problem reading ECMWF Grib file

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Subject: Re: New Ticket - [netCDFDecoders !FEG-733021]: Problem reading ECMWF Grib file
Date: Tue, 19 Dec 2006 13:59:11 -0700 (MST)

On Tue, 19 Dec 2006, address@hidden wrote:

> New Ticket: Problem reading ECMWF Grib file
>

this is a quasi-regular Grib1 grid, we decided not to do the work since
it's Grib1.  are we going to bring this up?  last quasi work was 3-5 days
effort.  i commented out the print in the code so it won't come up in IDV
and did another grib jar ci.

robb...





> Hi Robb-
>
> I have a GRIB file from ECMWF that does not give the correct
> navigation:
>
> /upc/share/testdata/grid/grib/grib1/data/ana_Z_20031006_00_ml.grib
>
> When I run Grib1Dump on this, it prints out:
>
> $ java  ucar.grib.grib1.Grib1Dump ana_Z_20031006_00_ml.grib
> GDS  numPV[ 0 ] = 0
> GDS  numPV[ 1 ] = 0
> GDS  numPV[ 2 ] = 16916
> GDS  numPV[ 3 ] = 0
> GDS  numPV[ 4 ] = 16934
> GDS  numPV[ 5 ] = 27875
> GDS  numPV[ 6 ] = 16959
> GDS  numPV[ 7 ] = -23082
> GDS  numPV[ 8 ] = 16991
> GDS  numPV[ 9 ] = -23792
> GDS  numPV[ 10 ] = 17030
> GDS  numPV[ 11 ] = 31674
> GDS  numPV[ 12 ] = 17076
> GDS  numPV[ 13 ] = -27240
> GDS  numPV[ 14 ] = 17130
> GDS  numPV[ 15 ] = -14480
> GDS  numPV[ 16 ] = 17170
> GDS  numPV[ 17 ] = -22545
> GDS  numPV[ 18 ] = 17175
> GDS  numPV[ 19 ] = 24461
> GDS  numPV[ 20 ] = 17181
> GDS  numPV[ 21 ] = 2532
> GDS  numPV[ 22 ] = 17187
> GDS  numPV[ 23 ] = -1429
> GDS  numPV[ 24 ] = 17196
> GDS  numPV[ 25 ] = -27779
> GDS  numPV[ 26 ] = 17207
> GDS  numPV[ 27 ] = 14993
> GDS  numPV[ 28 ] = 17220
> GDS  numPV[ 29 ] = 27995
> GDS  numPV[ 30 ] = 17236
> GDS  numPV[ 31 ] = -14440
> GDS  numPV[ 32 ] = 17257
> GDS  numPV[ 33 ] = 2623
> GDS  numPV[ 34 ] = 17282
> GDS  numPV[ 35 ] = 9314
> GDS  numPV[ 36 ] = 17313
> GDS  numPV[ 37 ] = 15928
> GDS  numPV[ 38 ] = 17351
> GDS  numPV[ 39 ] = -14657
> GDS  numPV[ 40 ] = 17399
> GDS  numPV[ 41 ] = -31574
> GDS  numPV[ 42 ] = 17427
> GDS  numPV[ 43 ] = 10933
> GDS  numPV[ 44 ] = 17431
> GDS  numPV[ 45 ] = -32251
> GDS  numPV[ 46 ] = 17436
> GDS  numPV[ 47 ] = -30046
> GDS  numPV[ 48 ] = 17442
> GDS  numPV[ 49 ] = 15630
> GDS  numPV[ 50 ] = 17448
> GDS  numPV[ 51 ] = -30688
> GDS  numPV[ 52 ] = 17455
> GDS  numPV[ 53 ] = 11634
> GDS  numPV[ 54 ] = 17461
> GDS  numPV[ 55 ] = -12461
> GDS  numPV[ 56 ] = 17468
> GDS  numPV[ 57 ] = 5070
> GDS  numPV[ 58 ] = 17473
> GDS  numPV[ 59 ] = -19591
> GDS  numPV[ 60 ] = 17478
> GDS  numPV[ 61 ] = 32047
> GDS  numPV[ 62 ] = 17482
> GDS  numPV[ 63 ] = 21426
> GDS  numPV[ 64 ] = 17485
> GDS  numPV[ 65 ] = 11036
> GDS  numPV[ 66 ] = 17486
> GDS  numPV[ 67 ] = -460
> GDS  numPV[ 68 ] = 17487
> GDS  numPV[ 69 ] = -12835
> GDS  numPV[ 70 ] = 17487
> GDS  numPV[ 71 ] = -24453
> GDS  numPV[ 72 ] = 17486
> GDS  numPV[ 73 ] = -32409
> GDS  numPV[ 74 ] = 17484
> GDS  numPV[ 75 ] = -32684
> GDS  numPV[ 76 ] = 17481
> GDS  numPV[ 77 ] = -20288
> GDS  numPV[ 78 ] = 17478
> GDS  numPV[ 79 ] = 10588
> GDS  numPV[ 80 ] = 17474
> GDS  numPV[ 81 ] = 888
> GDS  numPV[ 82 ] = 17469
> GDS  numPV[ 83 ] = 23155
> GDS  numPV[ 84 ] = 17464
> GDS  numPV[ 85 ] = 19232
> GDS  numPV[ 86 ] = 17458
> GDS  numPV[ 87 ] = -3272
> GDS  numPV[ 88 ] = 17453
> GDS  numPV[ 89 ] = 28866
> GDS  numPV[ 90 ] = 17447
> GDS  numPV[ 91 ] = -7808
> GDS  numPV[ 92 ] = 17442
> GDS  numPV[ 93 ] = 25179
> GDS  numPV[ 94 ] = 17437
> GDS  numPV[ 95 ] = 3790
> GDS  numPV[ 96 ] = 17432
> GDS  numPV[ 97 ] = 81
> GDS  numPV[ 98 ] = 17427
> GDS  numPV[ 99 ] = 19911
> GDS  numPV[ 100 ] = 17392
> GDS  numPV[ 101 ] = -20835
> GDS  numPV[ 102 ] = 17332
> GDS  numPV[ 103 ] = 31525
> GDS  numPV[ 104 ] = 17280
> GDS  numPV[ 105 ] = -902
> GDS  numPV[ 106 ] = 17238
> GDS  numPV[ 107 ] = -24934
> GDS  numPV[ 108 ] = 17205
> GDS  numPV[ 109 ] = 30154
> GDS  numPV[ 110 ] = 17181
> GDS  numPV[ 111 ] = 13654
> GDS  numPV[ 112 ] = 17106
> GDS  numPV[ 113 ] = 25814
> GDS  numPV[ 114 ] = 16961
> GDS  numPV[ 115 ] = -7259
> GDS  numPV[ 116 ] = 16757
> GDS  numPV[ 117 ] = -7610
> GDS  numPV[ 118 ] = 0
> GDS  numPV[ 119 ] = 0
> GDS  numPV[ 120 ] = 0
> GDS  numPV[ 121 ] = 0
> GDS  numPV[ 122 ] = 0
> GDS  numPV[ 123 ] = 0
> GDS  numPV[ 124 ] = 0
> GDS  numPV[ 125 ] = 0
> GDS  numPV[ 126 ] = 0
> GDS  numPV[ 127 ] = 0
> GDS  numPV[ 128 ] = 0
> GDS  numPV[ 129 ] = 0
> GDS  numPV[ 130 ] = 0
> GDS  numPV[ 131 ] = 0
> GDS  numPV[ 132 ] = 0
> GDS  numPV[ 133 ] = 0
> GDS  numPV[ 134 ] = 0
> GDS  numPV[ 135 ] = 0
> GDS  numPV[ 136 ] = 0
> GDS  numPV[ 137 ] = 0
> GDS  numPV[ 138 ] = 0
> GDS  numPV[ 139 ] = 0
> GDS  numPV[ 140 ] = 0
> GDS  numPV[ 141 ] = 0
> GDS  numPV[ 142 ] = 0
> GDS  numPV[ 143 ] = 0
> GDS  numPV[ 144 ] = 0
> GDS  numPV[ 145 ] = 0
> GDS  numPV[ 146 ] = 0
> GDS  numPV[ 147 ] = 0
> GDS  numPV[ 148 ] = 0
> GDS  numPV[ 149 ] = 0
> GDS  numPV[ 150 ] = 0
> GDS  numPV[ 151 ] = 0
> GDS  numPV[ 152 ] = 0
> GDS  numPV[ 153 ] = 0
> GDS  numPV[ 154 ] = 0
> GDS  numPV[ 155 ] = 0
> GDS  numPV[ 156 ] = 0
> GDS  numPV[ 157 ] = 0
> GDS  numPV[ 158 ] = 0
> GDS  numPV[ 159 ] = 0
> GDS  numPV[ 160 ] = 0
> GDS  numPV[ 161 ] = 0
> GDS  numPV[ 162 ] = 0
> GDS  numPV[ 163 ] = 0
> GDS  numPV[ 164 ] = 0
> GDS  numPV[ 165 ] = 0
> GDS  numPV[ 166 ] = 0
> GDS  numPV[ 167 ] = 0
> GDS  numPV[ 168 ] = 0
> GDS  numPV[ 169 ] = 0
> GDS  numPV[ 170 ] = 15695
> GDS  numPV[ 171 ] = -32329
> GDS  numPV[ 172 ] = 15902
> GDS  numPV[ 173 ] = 15596
> GDS  numPV[ 174 ] = 15990
> GDS  numPV[ 175 ] = -2748
> GDS  numPV[ 176 ] = 16148
> GDS  numPV[ 177 ] = -12304
> GDS  numPV[ 178 ] = 16173
> GDS  numPV[ 179 ] = -23504
> GDS  numPV[ 180 ] = 16212
>
> For a particular grid:
>
> --------------------------------------------------------------------
>                          Header : GRIB1
>                      Discipline : 0 Meteorological Products
>                    GRIB Edition : 1
>                     GRIB length : 130916
>              Originating Center : 98 European Center for Medium-Range
> Weather For
> ecasts (RSMC)
>          Originating Sub-Center : 0 WMO Secretariat
>              Product Definition : 0 Forecast/Uninitialized
> Analysis/Image Product
>
>              Parameter Category : -1 Meteorological Parameters
>                  Parameter Name : 131 U U velocity
>                 Parameter Units : m s^-1
>                  Reference Time : 2003-10-06T00:00:00Z
>                      Time Units : hour
>            Time Range Indicator : product valid at RT + P1
>                     Time 1 (P1) : 0
>                     Time 2 (P2) : 0
>         Generating Process Type : 203 Unknown
>                      Level Type : 109 hybrid level
>                   Level Value 1 : 60.0
>                   Level Value 2 : 0.0
>                      GDS Exists : true
>                      BMS Exists : false
>           Number of data points : 65160
>                       Grid Name : Latitude/Longitude Grid
>                       Grid Shape: 0 spherical
>           Spherical earth radius: 6367.47
>                              Nx : 360
>                              Ny : 181
>                             La1 : 90.0
>                             Lo1 : 0.0
>    Resolution & Component flags : 128
>                             La2 : -90.0
>                             Lo2 : 359.0
>                              Dx : -9999.0
>                              Dy : 1.0
>                   Scanning mode : 0
>
> notice that the Dx is -9999.0.  This ends up creating non-sensical
> longitudes.
>
> So, one issue is the debug messages printing out and the other is
> the bad longitude values.  This shows up in the tools UI as well as
> the IDV.  In the Tools UI, a dump of the longitude variable gives:
>
>
>     double lon(lon=360);
>       :units = "degrees_east";
>       :long_name = "longitude coordinate";
>       :standard_name = "longitude";
>       :grid_spacing = "-9999.0 degrees_east";
>       :_CoordinateAxisType = "Lon";
>
>   data:
>
>    {0.0, -9999.0, -19998.0, -29997.0, -39996.0, -49995.0, -59994.0,
> -69993.0, -79992.0, -89991.0, -99990.0, -109989.0, -119988.0, -129987.0,
> -139986.0, -149985.0, -159984.0, -169983.0, -179982.0, -189981.0,
> -199980.0, -209979.0, -219978.0, -229977.0, -239976.0, -249975.0,
> -259974.0, -269973.0, -279972.0, -289971.0, -299970.0, -309969.0,
> -319968.0, -329967.0, -339966.0, -349965.0, -359964.0, -369963.0,
> -379962.0, -389961.0, -399960.0, -409959.0, -419958.0, -429957.0,
> -439956.0, -449955.0, -459954.0, -469953.0, -479952.0, -489951.0,
> -499950.0, -509949.0, -519948.0, -529947.0, -539946.0, -549945.0,
> -559944.0, -569943.0, -579942.0, -589941.0, -599940.0, -609939.0,
> -619938.0, -629937.0, -639936.0, -649935.0, -659934.0, -669933.0,
> -679932.0, -689931.0, -699930.0, -709929.0, -719928.0, -729927.0,
> -739926.0, -749925.0, -759924.0, -769923.0, -779922.0, -789921.0,
> -799920.0, -809919.0, -819918.0, -829917.0, -839916.0, -849915.0,
> -859914.0, -869913.0, -879912.0, -889911.0, -899910.0, -909909.0,
> -919908.0, -929907.0, -939906.0, -949905.0, -959904.0, -969903.0,
> -979902.0, -989901.0, -999900.0, -1009899.0, -1019898.0, -1029897.0,
> -1039896.0, ....................
>
>
> There is another file in the directory (ana_Z_20031006_00.grib) from
> ECMWF which is on pressure coordinates. It does not have this problem.
>
> Don
> *************************************************************
> Don Murray                               UCAR Unidata Program
> address@hidden                        P.O. Box 3000
> (303) 497-8628                              Boulder, CO 80307
> http://www.unidata.ucar.edu/staff/donm
> *************************************************************
>
>
>
>
> Ticket Details
> ===================
> Ticket ID: FEG-733021
> Department: Support netCDF Decoders
> Priority: Normal
> Status: Open
> Link: 
> http://www.unidata.ucar.edu/esupport/staff/index.php?_m=tickets&_a=viewticket&ticketid=2889
>

===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================

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