Cubic Grids
The original expanded cubic grid proprosed by Sadourny (19??) was
based on the gnomonic projection (grid shown below). Although this
grid has excellent properties such as near uniform resolution and
perfect scaling with resolution it is not based on an orthogonal
coordinate system. Instead we followed the proposal of Rancic et
al. (19??) who use a conformal mapping to generate a cubic grid (shown
below).
Gnomonic cubic grid |
Conformal cubic grid |
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The conformal grid does not scale as well as the gnomonic grid but is
still orders of magnitude better than the latitude-longitude grid.