Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results

The rationale is given for a new gravimetric model of the New Zealand geoid to support a new vertical geodetic datum based on entirely different principles to the conventional use of tide gauges and geodetic levelling. The geoid model is currently being computed by Land Information New Zealand (LINZ...

Full description

Bibliographic Details
Main Authors: Amos, Matthew, Featherstone, Will
Format: Journal Article
Published: New Zealand Institute of Surveyors 2003
Subjects:
Online Access:http://hdl.handle.net/20.500.11937/31848
_version_ 1848753498105053184
author Amos, Matthew
Featherstone, Will
author_facet Amos, Matthew
Featherstone, Will
author_sort Amos, Matthew
building Curtin Institutional Repository
collection Online Access
description The rationale is given for a new gravimetric model of the New Zealand geoid to support a new vertical geodetic datum based on entirely different principles to the conventional use of tide gauges and geodetic levelling. The geoid model is currently being computed by Land Information New Zealand (LINZ) in close collaboration with the Western Australian Centre for Geodesy. The data to be used in this new geoid model comprise >40,000 land and >1.3M ship-track gravity data points, a 56 m-resolution digital elevation model (DEM), a 2' 2' grid of marine gravity anomalies derived from multimission satellite altimetry, and a hybrid global geopotential model derived from EGM96 and the new EIGEN-2 model. A preliminary geoid model has been computed from these data using spectral techniques with modified kernels, and comparisons with existing GPS-levelling data on the 13 different vertical datums used in New Zealand indicate an overall precision of ~ 35 cm, which can be improved with the more sophisticated data pre-processing currently underway. This preliminary geoid model has been used to estimate preliminary offsets among the 13 different vertical datums used throughout New Zealand. Importantly, the standard deviations are less than the computed offsets, which indicates that statistically significant offsets can be computed with the proposed approaches.
first_indexed 2025-11-14T08:25:28Z
format Journal Article
id curtin-20.500.11937-31848
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T08:25:28Z
publishDate 2003
publisher New Zealand Institute of Surveyors
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-318482017-01-30T13:27:47Z Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results Amos, Matthew Featherstone, Will New Zealand geoid vertical datum The rationale is given for a new gravimetric model of the New Zealand geoid to support a new vertical geodetic datum based on entirely different principles to the conventional use of tide gauges and geodetic levelling. The geoid model is currently being computed by Land Information New Zealand (LINZ) in close collaboration with the Western Australian Centre for Geodesy. The data to be used in this new geoid model comprise >40,000 land and >1.3M ship-track gravity data points, a 56 m-resolution digital elevation model (DEM), a 2' 2' grid of marine gravity anomalies derived from multimission satellite altimetry, and a hybrid global geopotential model derived from EGM96 and the new EIGEN-2 model. A preliminary geoid model has been computed from these data using spectral techniques with modified kernels, and comparisons with existing GPS-levelling data on the 13 different vertical datums used in New Zealand indicate an overall precision of ~ 35 cm, which can be improved with the more sophisticated data pre-processing currently underway. This preliminary geoid model has been used to estimate preliminary offsets among the 13 different vertical datums used throughout New Zealand. Importantly, the standard deviations are less than the computed offsets, which indicates that statistically significant offsets can be computed with the proposed approaches. 2003 Journal Article http://hdl.handle.net/20.500.11937/31848 New Zealand Institute of Surveyors restricted
spellingShingle New Zealand
geoid
vertical datum
Amos, Matthew
Featherstone, Will
Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title_full Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title_fullStr Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title_full_unstemmed Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title_short Preparations for a New Gravimetric Geoid Model of New Zealand, and Some Preliminary Results
title_sort preparations for a new gravimetric geoid model of new zealand, and some preliminary results
topic New Zealand
geoid
vertical datum
url http://hdl.handle.net/20.500.11937/31848