This page is under construction...explanation and links will be added in the coming days and weeks...feedback welcome!
...
...
The lat_typ options for global grids are "eqa" for Equi-angular, "fv" for Finite Volume, and "gss" for Gaussian. An equiangular grid has constant spacing in latitude, and may have any number of latitudes. There is point centered at the poles in an Equi-angular grid. An FV grid is nearly identical to an Equi-angular grid, with some important data and metadata differences at the poles. FV grids must have an odd number of latitudes because the first and last latitudes have special properties (and span half the width
of the other latitudes), whereas the Equiangular grid may have any number of latitudesare rectangular representations of equi-angular (in latitude) grids that have a "cap" point at each pole. In order to add-up to the same latitude across the cap as in the rest of the zones, the polar cells in the FV rectangular representation on disk must span half the width of the other latitudes. Moreover, that is why the center and outer interface of the polar points in the FV grid are both labeled as 90 degrees. Gaussian grids must have an even number of latitudes. The lon_typ options for global grids are "grn_ctr" and "180_ctr" for the first gridcell centered at Greenwich or 180 degrees, respecitvely. And "grn_wst" and "180_wst" for Greenwich or 180 degress lying on the western edge of the first gridcell.
...