I am seeking advice on working with world data sets where the GCS has a positive range (0 degrees to 360 degrees). The data I am working with are NetCDF oceanographic data and have positive coordinate values as mentioned. When displayed in a normal GCS WGS84 in ESRI's ArcGIS 10, it is offset from other data that exist in the range of -180 to 180. If I reproject it, gaps occur around the prime meridian (mostly due to its origins, sometimes as far off as 25 degrees W). My thought is to create a custom projection/coordinate system that has the positive values and hope that other world data sets reproject on the fly just fine. Does anyone see any issues with this or have other solutions? Hope this makes sense. I appreciate any help in advance.
** Update ** This is a screenshot of a countries data set with graticule on top to show the normal CRS of GCS. Just importing the NetCDF data as-is brings it in but the values don't start until 20.5 degrees east of the Prime Meridian.
Normal GCS http://grafa.co/rnd/img/GCS_Normal.png
If I choose to use the NetCDF's CRS (which is actually the same) it will reproject the world data on the fly if it is defined. Note the graticule is undefined so it does not reproject. Sort of reprojected GCS http://grafa.co/rnd/img/GCS_Other.png
But then if I try to reproject everything to a normal GCS with negative values, it's like wrapping a flat map of the data around the world and then it disappears when it hits the Prime Meridian. Sort of reprojected GCS http://grafa.co/rnd/img/reprojected.png
Now, I know there are no values from 0-20.5 as is stated in the metadata. But why can't the values from rest of the data display in the gap? I even tried a Shift in the Raster Tools to no avail.
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