Document Type : Research Paper

Author

Abstract

The geoid model currently used by Australia has been calculated using combination of the global model of OSU91A and the Australian Gravity Information Database published in 1980. Currently, due to the availability of advanced data and more accurate computational methods, Australian geoid accuracy can be improved. In 1998, the Australian Research Council allocated a budget for a group project to seek a new generation of gravimetric geoid model for Australia.
While presenting some of the research that is currently in its final stages, this paper discusses providing new data, selecting the most appropriate global model that the new Australian geoid will be based on, and a Digital Terrain Model (DTM) to calculate the effects of the Earth on geoid. Improving the geoid model makes it possible for field surveyors to implement high-precision topographic mapping with the aid of GPS on the basis of Australian elevation (Oustralian Height Datum-AHD) while decreasing required time and cost.
First-hand reports and experiences suggest that the use of gravimetric geoid with along with GPS, as an option for immediate alignment, can bring about save of time and cost in a range between 100% and 300%.