2
Geoid height above reference ellipsoid
geoid_height_above_reference_ellipsoid
2017-07-24 14:36:59.0
accepted
false
The geoid is a surface of constant geopotential with which mean sea level would coincide if the ocean were at rest. (The volume enclosed between the geoid and the sea floor equals the mean volume of water in the ocean). In an ocean GCM the geoid is the surface of zero depth, or the rigid lid if the model uses that approximation. A reference ellipsoid is a regular mathematical figure that approximates the irregular shape of the geoid. A number of reference ellipsoids are defined for use in the field of geodesy. To specify which reference ellipsoid is being used, a grid_mapping variable should be attached to the data variable as described in Chapter 5.6 of the CF Convention.