Resolution flag:
 0    Direction increments not given. 
 128  Direction increments given.

0  Regular grid.
1  Quasi-regular (reduced) grid.
At the moment, quasi-regular (reduced) latitude/longitude grids are
not unambiguously defined. The resolution flag field indicates whether
or not both direction increments are given; at least one must be given,
as grids are only allowed to be irregular in one direction.

Earth flag:
 0   Earth assumed spherical with radius 6367.47 km.
 64  Earth assumed oblate spheroidal with size as determined by IAU in 1965:
       6378.160km,   6356.775km,   f=1/297.0

Components flag:
 0  Resolved u and v components of vector quantities relative to easterly
    and northerly directions.
 8  Resolved u and v components of vector quantities relative to the
    defined grid in the direction of increasing x and y (or i and j)
    coordinates respectively.

For a quasi-regular (reduced) grid, the number of points along each parallel
must be defined. The number of parallels is given by Nj above.
Alternatively, this may be the number of pointqs along each meridian, where
the number of meridians is given by Ni above.q