|2.5-min gravity grid of N. America
|The dgrav gridded data set was produced by NGDC by regridding the Decade of North
American (DNAG) 6-km gravity grid of N. America. A grid cell dimension of 2.5 minutes
of longitude and latitude was used in this regridding process. In order to facilitate
the comparison of the various regridded data, a geodetic reference system was used
as the most suitable common coordinate frame.