Dave, I've been working on a similar problem: using NcML to make the HDF remote sensing imagery served by the NOAA Coastwatch East Coast OpenDAP server CF-compliant. I have been using aggregation type="union" to join the HDF data with a netcdf file that contains the lon/lat values, since Coastwatch uses the same non-uniform lon/lat grid (it's a uniform mercator grid). The NcML looks like this: <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";> <aggregation type="union"> <netcdf location="http://coast-enviro.er.usgs.gov/models/gom_interop/coastwatch_northeast_lonlat.nc"/> <netcdf location="http://coastwatch.chesapeakebay.noaa.gov/dap/edac/avhrr/data/2008_135_0921_noaa15_ex1_sst.hdf"/> </aggregation> </netcdf> I can also aggregate the HDF5 images along a virtual time dimension and then union with the netcdf file that has the lon/lat values, and it works -- only remaining issue is that the scale_factor is lost for some reason, which I'm looking into. Try getting http://coast-enviro.er.usgs.gov/models/share/coastwatch.zip and running "test_sst", then looking at the two NcML files "sst.ncml" -Rich On Fri, May 30, 2008 at 9:20 AM, David Robertson <robertson@xxxxxxxxxxxxxxxxxx> wrote: > Hi, > > If I want to serve aggregated HDF5 files, do I have to specify the > coordinate system (grid) with NcML, or is there a way to construct the > HDF5 file so THREDDS can get the coordSys directly from the HDF5 file? I > ask because if my only option is NcML I will ask my "data source" to > create NetCDF files instead since the coverage area is 1222 x 1183 > points and they are not equal spaced. > > Thanks, > Dave > _______________________________________________ > thredds mailing list > thredds@xxxxxxxxxxxxxxxx > For list information or to unsubscribe, visit: > http://www.unidata.ucar.edu/mailing_lists/ > -- Dr. Richard P. Signell (508) 457-2229 USGS, 384 Woods Hole Rd. Woods Hole, MA 02543-1598
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