Re: NetCDF file won't open.

Hi Aaron-

Aaron Dalton wrote:
I'm creating a CF-1.0 complient dataset for MODIS NDVI Data spanning the period of record. Unfortunately IDV doesn't seem to recognize any of the data elements in the file. Attatched is the NetCDF header. I've run through the CF-1.0 compliance checker and the file checks out. What am I doing wrong? Are there any undocumented gotcha's that I need to watch out for?

The problem is the IDV has not implemented the Albers_Equal_Area
projection yet.  Could you send me a pointer to your file and
we can look into adding that?

Also, just as a point of clarification, the CF compliance checkers
do not check that all necessary metadata are in there, so sometimes
just because it passes the CF checker, doesn't mean that the metadata
needed by the IDV is complete.  I think yours is okay, but I just
want to point this out to the list.

Don Murray

Thanks, Aaron Dalton

netcdf NDVI_ALL {
dimensions:
        x = 3531 ;
        y = 1720 ;
        time = 128 ;
variables:
        int Albers_Equal_Area ;
                Albers_Equal_Area:grid_mapping_name = 
"albers_conical_equal_area" ;
                Albers_Equal_Area:standard_parallel = 37., 39. ;
                Albers_Equal_Area:longitude_of_central_meridian = -79.5 ;
                Albers_Equal_Area:latitude_of_projection_origin = 38. ;
        char projectionCoordSys ;
                projectionCoordSys:_CoordinateAxes = "time y x" ;
                projectionCoordSys:_CoordinateTransforms = "Albers_Equal_Area" ;
        short time(time) ;
                time:long_name = "observation time" ;
                time:units = "days since 2000-01-01" ;
                time:_CoordinateAxisType = "Time" ;
        double y(y) ;
                y:units = "m" ;
                y:long_name = "y coordinate of projection" ;
                y:standard_name = "projection_y_coordinate" ;
                y:_CoordinateAxisType = "GeoY" ;
        double x(x) ;
                x:units = "m" ;
                x:long_name = "x coordinate of projection" ;
                x:standard_name = "projection_x_coordinate" ;
                x:_CoordinateAxisType = "GeoX" ;
        double lat(y, x) ;
                lat:units = "degrees_north" ;
                lat:long_name = "latitude coordinate" ;
                lat:standard_name = "latitude" ;
                lat:_CoordinateAxisType = "Lat" ;
        double lon(y, x) ;
                lon:units = "degrees_east" ;
                lon:long_name = "longitude coordinate" ;
                lon:standard_name = "longitude" ;
                lon:_CoordinateAxisType = "Lon" ;
        short NDVI(time, y, x) ;
                NDVI:units = "1" ;
                NDVI:long_name = "NDVI" ;
                NDVI:_FillValue = -3000 ;
                NDVI:valid_min = -2000 ;
                NDVI:valid_max = 10000 ;
                NDVI:scale_factor = 0.0001 ;
                NDVI:coordinates = "lat lon" ;
                NDVI:grid_mapping = "Albers_Equal_Area" ;
                NDVI:_CoordinateSystems = "projectionCoordSys" ;

// global attributes:
                :Conventions = "CF-1.0" ;
                :title = "Modis NDVI composite data" ;
                :institution = "VirginiaView, Virginia Tech" ;
                :DataType = "GRID" ;
}

____________________
Aaron Dalton Computer Science/Mathematics
E-mail: aadalton@xxxxxx
Cell: (540) 815-9828
AIM: adalt0n