id summary reporter owner description type status priority milestone component version severity resolution keywords cc 5084 duplicate nodata metadata in netcdf files copied with gdal_translate etourigny etourigny "when a netcdf file has nodata field defined in missing_value metadata and is copied using gdal_translate(or CreateCopy()), a new nodata value is added in _FillValue metadata. If the new nodata value is different this can lead to conflicting nodata values, depending on softawre used. example using trmm.nc in autotest (extra output deleted): {{{ $ ncatted -O -a missing_value,pcp,a,f,0 trmm.nc trmm-miss.nc $ ncatted -a _FillValue,pcp,d,, trmm-miss.nc $ gdal_translate -a_nodata -1 -of netcdf trmm-miss.nc trmm-miss2.nc Input file size is 40, 40 0...10...20...30...40...50...60...70...80...90...100 - done. $ ncdump -h trmm-miss2.nc netcdf trmm-miss2 { dimensions: lon = 40 ; lat = 40 ; time = 1 ; variables: ... float pcp(time, lat, lon) ; pcp:long_name = ""precipitation:Precipitation"" ; pcp:_FillValue = -1.f ; pcp:comments = ""Unknown1 variable comment"" ; pcp:grid_name = ""grid-1"" ; pcp:level_description = ""Earth surface"" ; pcp:missing_value = 0 ; pcp:time_statistic = ""instantaneous"" ; } $ gdalinfo trmm-miss2.nc Driver: netCDF/Network Common Data Format Files: trmm-miss2.nc ... Band 1 Block=40x1 Type=Float32, ColorInterp=Undefined NoData Value=-1 Metadata: _FillValue=-1 missing_value=0 }}} solution is to strip _FillValue and missing_value from metadata when copying, and let driver assign proper metadata (_FillValue)" defect closed normal 1.10.1 default unspecified normal fixed netcdf, nodata