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I've downloaded and extracted AMSR2 sea ice concentration netCDF files from here. Then I tried using the "Define Projection" tool in ArcGIS 10.4 (on Windows 10) to define their spatial reference (and "Edit" spatial reference in ArcCatalog). Based on the documentation, I guessed it was a custom NSIDC North Pole Stereographic projection.

Unfortunately it does not overlay with my other data in that projection at all. Under "Grid Description" in the documentation, it says

3. Grid Description

The data is displayed in two polar stereographic maps per day, one for the Arctic (Arc) and one for the Antarctic (Ant). Python PYRESAMPLE is used to derive a 3.125km grid according to the (corner) grid coordinates provided by NSIDC (http://nsidc.org/data/polar_stereo/ps_grids.html).

  • Polar stereographic projection with the projection plane intersecting the earth at 70 degree and using the Hughes ellipsoid; with the radius of 6378.273 km and an eccentricity (e) of 0.081816153, follows a semi-minor axis of 6356.88944891.

  • Corner coordinates northern hemisphere ('Arc'):

    lon 168.35, lat 31.00, lon 102.34, lat 31.38, lon -9.98, lat 34.36, lon -80.74, lat 33.94

  • Corner coordinates southern hemisphere ('Ant'):

    lon -42.24, lat -39.25, lon 42.24, lat -39.25, lon 135.00, lat -41.46, lon -135.00, lat -41.46

The values for semi-major axis, semi-minor axis, projection plane, and the >corner coordinates are used to calculate the pixel loacations with the PYRESAMPLE >package.

The geographic coordinates are provided in the following netCDF-file: LongitudeLatitudeGrid_3.125km_Arctic.nc

The polar stereographic projection details are the same as my NSIDC projection, but I don't know what to do with these corner coordinates.

I downloaded the "LongitudeLatitudeGrid_3.125km_Arctic.nc" file. It projects neatly on top of my other NetCDFs, and I can make raster layers for latitude and longitude, but how do I use these to build the coordinate system into rasters from the NetCDFs?

  • My .nc files display well in Panoply, but not in NOAA's Weather and Climate Toolkit, interestingly enough. – Wassadamo Apr 5 '17 at 16:40

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