non-Uniform Grids and Triangular Mesh Conversion
The GEODESIC grid used in the examples on this page is non-uniform grid. It is better to convert this grid to a triangular mesh (available since NCL version 4.2.0.a032) rather than interpolate it to a uniform grid before contouring. Note that only contouring is available with triangular mesh conversion at this time.If the input array to a gsn_csm graphical interface is one dimensional, NCL automatically uses triangular mesh conversion. The lat/lon information must be provided by setting:
sfXArray and sfYArray.

