Using "double" for lon,lat for GALEON WCS NetCDF3 files

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GALEON-folk,
I think it might be a good idea to use type "double" for "lon" and "lat" when requesting "format=NetCDF3" from the Galeon WCS.
I used the remote data serving capability of the GALEON WCS to grab a piece of a CF-compliant NetCDF file on my own OpenDAP server. 

I asked for both format=NetCDF3 and format=GeoTIFF.
I then put the resulting NetCDF file on my OpenDAP site and used GALEON WCS to grab another piece of data as GeoTIFF.
The pixel resolution on the resulting GeoTIFFs should be the same, but it is different, because the original NetCDF had type "double" and this is 3 arc second data from the NGDC Coastal Relief Model. 


[rsignell@ricsigdtlx bathy]$ gdalinfo file1.tif
Driver: GTiff/GeoTIFF
Size is 541, 421
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.2572235629972,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-70.599602,41.550406)
Pixel Size = (0.00083333,-0.00083333)


FILE2:

[rsignell@ricsigdtlx bathy]$ gdalinfo file2.tif
Driver: GTiff/GeoTIFF

Size is 541, 421
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.2572235629972,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-70.599602,41.550407)
Pixel Size = (0.00083160,-0.00083542)
It's only a fraction of a meter, but it's still a bit unsettling to see the pixel resolution go from uniform to non-uniform. 

Here's the script I used:

#!/bin/bash
# Example script to grab gridded Coastal Relief Model data via the GALEON WCS 

# Get Vineyard Sound bathy from *my* CF-Compliant, DODS-served
# Coastal Relief Model data via GALEON.  COOL!!!!

# format=GeoTIFFfloat
curl -o file1.tif 'http://motherlode.ucar.edu:8080/thredds/wcs/?dataset=http://stellwagen.er.usgs.gov/cgi-bin/nph-dods/rps/data/crm_geo.nc&request=GetCoverage&version=1.0.0&service=WCS&format=GeoTIFFfloat&coverage=z&bbox=-70.6,41.2,-70.15,41.55' 

# format=NetCDF3
curl -o file1.nc 'http://motherlode.ucar.edu:8080/thredds/wcs/?dataset=http://stellwagen.er.usgs.gov/cgi-bin/nph-dods/rps/data/crm_geo.nc&request=GetCoverage&version=1.0.0&service=WCS&format=NetCDF3&coverage=z&bbox=-70.6,41.2,-70.15,41.55' 


-Rich
--
Richard P. Signell
U.S. Geological Survey       Phone: (508) 457-2229
384 Woods Hole Road          Fax:   (508) 457-2310
Woods Hole, MA  02543-1598

#!/bin/bash
# Example script to grab gridded Coastal Relief Model data via the GALEON WCS

# Get Vineyard Sound bathy from *my* CF-Compliant, DODS-served 
# Coastal Relief Model data via GALEON.  COOL!!!!

# format=GeoTIFFfloat 

curl -o vs_bathy.tif 
'http://motherlode.ucar.edu:8080/thredds/wcs/?dataset=http://stellwagen.er.usgs.gov/cgi-bin/nph-dods/rps/data/crm_geo.nc&request=GetCoverage&version=1.0.0&service=WCS&format=GeoTIFFfloat&coverage=z&bbox=-70.6,41.2,-70.15,41.55'

# format=NetCDF3

curl -o vs_bathy.nc 
'http://motherlode.ucar.edu:8080/thredds/wcs/?dataset=http://stellwagen.er.usgs.gov/cgi-bin/nph-dods/rps/data/crm_geo.nc&request=GetCoverage&version=1.0.0&service=WCS&format=NetCDF3&coverage=z&bbox=-70.6,41.2,-70.15,41.55'

# Rich Signell (rsignell@xxxxxxxx)
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