AUSGeoid98 Geoid-Ellipsoid Separation Interpolation

Compute an N value

Enter your data in the fields below in the format of Degrees, Minutes & Seconds.

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Help Computing an N value

1. Enter the latitude and longitude of the site in the fields provided.
2. The latitude and longitude are entered as degrees, minute and seconds.
3. Every field must contain an entry (enter a zero, not a blank, for empty fields).
4. South latitudes are negative, so the degrees of latitude must be entered as a negative number.

The resulting geoid-ellipsoid separation is interpolated from the AUSGeoid98 2' grid of geoid-ellipsoid separations, using Geoscience Australia's Winter (Windows Interpolation) software and is in terms of the Geodetic Reference System 1980 (GRS80) ellipsoid, suitable for use with GPS (GDA94/WGS84).

WINTER uses bi-cubic interpolation (using 16 surrounding data points) but will revert to bi-linear interpolation if the edge of the AUSGeoid grid of data is reached and only 4 surrounding data points are available.

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