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pythongdalgribcdo-climate

Possible bug in GDAL?

Given this file:

http://mtarchive.geol.iastate.edu/2019/02/18/mrms/ncep/GaugeCorr_QPE_01H/GaugeCorr_QPE_01H_00.00_20190218-150000.grib2.gz

… I get different output depending on the software I use.

wgrib2 2019021815.grib2 -csv wgrib2.csv

and

cdo outputtab,date,time,lat,lon,value 2019021815.grib2 > cdo.txt

both output:

-3 (undefined) :  8,869,250 records
0              : 14,848,865 records
Other values   :    781,885 records
___________________________________
Total          : 24,500,000 records

However:

gdal_translate.exe -of xyz 2019021815.grib2 gdal.csv

outputs -3 for all 24,500,000 records.

I get the same result if I parse the file using Python + GDAL.

Is this a bug in GDAL? I'd like to be able to parse these files using Python.

I'm using Windows for wgrib2, which can be downloaded from ftp://ftp.cpc.ncep.noaa.gov/wd51we/wgrib2/Windows_7/

I'm also using Windows for GDAL, which can be downloaded from https://gdal.org/download.html

I'm using Linux for cdo, which can be downloaded from https://code.mpimet.mpg.de/projects/cdo/

Solution

  • As you suggest, this seems to be a bug in GDAL. I tested the same command using GDAL 2.4.2, and it works. The change log for 2.4.0 points to several fixes to the GRIB driver.

    GRIB driver: