A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania
The adoption of local mean sea level (MSL) at multiple tide-gauges as a zero reference level for the Australian Height Datum (AHD) has resulted in a spatially variable offset between the geoid and the AHD. This is caused primarily by sea surface topography (SSTop), which has also resulted in the AHD...
| Main Authors: | , |
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| Format: | Journal Article |
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Taylor and Francis
2012
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| Online Access: | http://hdl.handle.net/20.500.11937/15509 |
| _version_ | 1848748912226074624 |
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| author | Featherstone, Will Filmer, Michael |
| author_facet | Featherstone, Will Filmer, Michael |
| author_sort | Featherstone, Will |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The adoption of local mean sea level (MSL) at multiple tide-gauges as a zero reference level for the Australian Height Datum (AHD) has resulted in a spatially variable offset between the geoid and the AHD. This is caused primarily by sea surface topography (SSTop), which has also resulted in the AHD on the mainland being offset vertically from the AHD on the island of Tasmania. Errors in MSL observations at the 32 tide-gauges used in the AHD and the temporal bias caused by MSL observations over different time epochs also contribute to the offset, which previous studies estimate to be between ~+100 mm and ~+400 mm (AHD on the mainland above the AHD on Tasmania). This study uses five SSTop models (SSTMs), as well as GNSS and two gravimetric quasigeoid models, at tide-gauges/tide-gauge benchmarks to re-estimate the AHD offset, with the re-evaluated offset between −61 mm and +48 mm. Adopting the more reliable CARS2006 oceanographic-only SSTM, the offset is −12 ± 11 mm, an order of magnitude less than three previous studies that used geodetic data alone. This suggests that oceanographically derived SSTMs should be considered as a viable alternative to geodetic-only techniques when attempting to unify local vertical datums. |
| first_indexed | 2025-11-14T07:12:35Z |
| format | Journal Article |
| id | curtin-20.500.11937-15509 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:12:35Z |
| publishDate | 2012 |
| publisher | Taylor and Francis |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-155092017-09-13T15:59:13Z A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania Featherstone, Will Filmer, Michael The adoption of local mean sea level (MSL) at multiple tide-gauges as a zero reference level for the Australian Height Datum (AHD) has resulted in a spatially variable offset between the geoid and the AHD. This is caused primarily by sea surface topography (SSTop), which has also resulted in the AHD on the mainland being offset vertically from the AHD on the island of Tasmania. Errors in MSL observations at the 32 tide-gauges used in the AHD and the temporal bias caused by MSL observations over different time epochs also contribute to the offset, which previous studies estimate to be between ~+100 mm and ~+400 mm (AHD on the mainland above the AHD on Tasmania). This study uses five SSTop models (SSTMs), as well as GNSS and two gravimetric quasigeoid models, at tide-gauges/tide-gauge benchmarks to re-estimate the AHD offset, with the re-evaluated offset between −61 mm and +48 mm. Adopting the more reliable CARS2006 oceanographic-only SSTM, the offset is −12 ± 11 mm, an order of magnitude less than three previous studies that used geodetic data alone. This suggests that oceanographically derived SSTMs should be considered as a viable alternative to geodetic-only techniques when attempting to unify local vertical datums. 2012 Journal Article http://hdl.handle.net/20.500.11937/15509 10.1080/01490419.2011.634961 Taylor and Francis fulltext |
| spellingShingle | Featherstone, Will Filmer, Michael A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title | A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title_full | A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title_fullStr | A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title_full_unstemmed | A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title_short | A re-evaluation of the offset in the Australian Height Datum between mainland Australia and Tasmania |
| title_sort | re-evaluation of the offset in the australian height datum between mainland australia and tasmania |
| url | http://hdl.handle.net/20.500.11937/15509 |