AUSGeoid98

AUSGeoid98 has been replaced by AUSGeoid09 as the national geoid model for Australia. AUSGeoid98 was based predominantly on satellite and terrestrial gravity observations which were a best fit of the geoid over Australia (Featherstone et al 2001). Although AUSGeoid98 was designed to assist GPS users to convert ellipsoidal heights to AHD heights it did not account for the one metre offset trend between the geoid and the AHD. As a result, when using AUSGeoid98, GPS users could only retrieve AHD heights to within ±0.5metres. Using AUSGeoid09, users can compute AHD heights to within ±0.03m across most of Australia.

Map of Australia showing the AUSGeoid98 values throughout the country. The major feature is the trend from the north-east with a high of approximately 70 m to the south-west which has a value of approximately -30 m.

AUSGeoid98

Topic contact: geodesy@ga.gov.au Last updated: May 8, 2013