GPS Heighting in Okavango Delta
Publication: Journal of Surveying Engineering
Volume 124, Issue 4
Abstract
For the past three years, an annual campaign of global positioning system (GPS) measurements has been mounted in the Okavango Delta in Botswana, as part of a multidisciplinary research project. The project examines the hydrology, sedimentology, and plant ecology of the wetland. Critical to the project is the determination of the relative heights of water gauges and other points within this 22,000 km2 area. GPS has proven to be a key technology in achieving this aim. Nevertheless, its use does introduce a complication in that the heights derived using GPS are ellipsoidal, whereas orthometric heights are required in the context of modeling water flow. Conversion from one type of height to the other requires an accurate model of the geoid, but this is not easy to produce in such a data-scarce area. In this paper, the writers describe the GPS surveys and the adjustment and connection of the GPS networks to existing survey control. Two geoid models for the region are assessed and their significance evaluated.
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Information & Authors
Information
Published In
Journal of Surveying Engineering
Volume 124 • Issue 4 • November 1998
Pages: 145 - 155
Copyright
Copyright © 1998 American Society of Civil Engineers.
History
Published online: Nov 1, 1998
Published in print: Nov 1998
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