Conversion of spherical harmonics and gaussian grid data to a regular lon-lat grid

• Compare gridded lon-lat data (1x1 degree) directly from MARS (ECMWF) to gridded lon-lat data derived with ecll from spherical harmonic (T159) data.
• Download v1.4 of ecll: ecll_v1.4.tar. This requires the library emoslib! ecll has been written by Arjo Segers.