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Tom, > First of all, the NetCDF-3 library should not be able to recognize a > NetCDF-4 (HDF5) file right? If that's correct maybe we just need > to update our v4 libraries. Yes, you need an ncdump compiled against the netCDF-4 library to recognize netCDF-4 files. --Russ > Unidata netCDF Support wrote: > > Hi Tom, > > > > > >> We have a NetCDF file which ncdump fails to recognize as a > >> valid file. I can open the file with the java-netcdf library using > >> toolsUI-4.0.jar. I'm not sure if this is a v3/4 or 32/64bit > >> compatibility problem. We found that neither NetCDF-3 or 4 > >> will ncdump this file: > >> > >> ftp.ssec.wisc.edu/pub/incoming/MSG_SEVIRI_2008157_1200_AWG_SST.nc > >> TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION.nc > >> > > > > You've provided 2 file names, so I'm not sur which one is causing > > ncdump problems. > > > > I downloaded the first one and ncdump seems to recognize it as a > > netCDF-4 problem and read the metadata just fine: > > > > $ ls -l MSG_SEVIRI_2008157_1200_AWG_SST.nc > > -rw-r--r-- 1 russ ustaff 220481910 Jul 1 09:16 > > MSG_SEVIRI_2008157_1200_AWG_SST.nc > > $ ncdump -k MSG_SEVIRI_2008157_1200_AWG_SST.nc > > netCDF-4 > > $ ncdump -h MSG_SEVIRI_2008157_1200_AWG_SST.nc > > netcdf MSG_SEVIRI_2008157_1200_AWG_SST { > > dimensions: > > Columns = 3712 ; > > Rows = 3712 ; > > variables: > > float Latitude(Columns, Rows) ; > > Latitude:long_name = "Latitude" ; > > Latitude:units = "degrees" ; > > Latitude:comments = "Pixel latitude (degree)" ; > > float Longitude(Columns, Rows) ; > > Longitude:long_name = "Longitude" ; > > Longitude:units = "degrees" ; > > Longitude:comments = "Pixel Longitude (degree)" ; > > float SST_Regression(Columns, Rows) ; > > SST_Regression:Units = "K" ; > > SST_Regression:Comments = "Sea Surface Temperature (SST) > > derived from SEVIRI BTs using regression technique" ; > > SST_Regression:long_name = "sst regression" ; > > SST_Regression:_FillValue = -999.999f ; > > SST_Regression:missing_value = -999.999f ; > > float SST_Physical(Columns, Rows) ; > > SST_Physical:Units = "K" ; > > SST_Physical:Comments = "Sea Surface Temperature (SST) derived > > from SEVIRI BTs using inversion (physical) method" ; > > SST_Physical:long_name = "sst physical" ; > > SST_Physical:_FillValue = -999.999f ; > > SST_Physical:missing_value = -999.999f ; > > SST_Physical:valid_range = 0.f, 400.f ; > > > > // global attributes: > > :Conventions = "CF-1.4" ; > > :Title = "AIT SST Product" ; > > :Source = "AIT_Framework" ; > > } > > > > Similarly for the second file, I can't duplicate the problem you are > > seeing: > > > > $ ls -l TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION.nc > > -rw-r--r-- 1 russ ustaff 27503920 Jul 1 09:25 > > TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION.nc > > you have mail in /var/mail/russ > > $ ncdump -k TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION.nc > > netCDF-4 > > $ ncdump -h TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION.nc > > netcdf TERRA_MODIS_2005155_3257_AWG_AEROSOL_DETECTION { > > dimensions: > > Columns = 1354 ; > > Rows = 2030 ; > > variables: > > float Latitude(Columns, Rows) ; > > Latitude:long_name = "Latitude" ; > > Latitude:units = "degrees" ; > > Latitude:comments = "Pixel latitude (degree)" ; > > float Longitude(Columns, Rows) ; > > Longitude:long_name = "Longitude" ; > > Longitude:units = "degrees" ; > > Longitude:comments = "Pixel Longitude (degree)" ; > > byte Smoke(Columns, Rows) ; > > byte Dust(Columns, Rows) ; > > } > > > > I'm using the latest ncdump from our snapshot release, but I don't > > think that's relevant here, unless you've identified a bug in an > > older version of ncdump we don't know about. > > > > What's the ncdump version (check the last line of the output from > > ncdump --version)? > > > > --Russ > > > > Russ Rew UCAR Unidata Program > > address@hidden http://www.unidata.ucar.edu > > > > > > > > Ticket Details > > =================== > > Ticket ID: AZT-127023 > > Department: Support netCDF > > Priority: Normal > > Status: Closed > > > > > > Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: AZT-127023 Department: Support netCDF Priority: Normal Status: Closed