Australia to shift co-ordinates to match up with GPS


Australia will shift its longitude and latitude to close a gap between land-based co-ordinates and those used by satellites.

The problem has arisen as satellites use location data based on global lines of longitude and latitude that do not move as tectonic plates shift.

Local co-ordinates are based on fixed positions on the land that move with the continent. As Australia moves about 7cm north each year due to the movement of the Indo-Australia Plate, the result is a discrepancy of about 1 metre has grown between the two measurements.

Changing co-ordinates so that they match is important as we come to rely on global positioning systems (GPS) more and more. It will improve the accuracy of satellite navigation systems, but more importantly for future-proofing the country, it will allow Australia's self-driving cars to operate correctly.

Dan Jaksa of Geoscience Australia said "If you want to start using driverless cars, accurate map information is fundamental.

"We have tractors in Australia starting to go around farms without a driver, and if the information about the farm doesn't line up with the co-ordinates coming out of the navigation system there will be problems."

Since the country's local co-ordinate system was last updated in 1994, its plate has moved 1.5m north. So on 1 January 2017, Australia's data points will move 1.8m north.

The discrepancy means that the local and global positions should line up in 2020, at which point a new automated system will be implemented that will adapt to allow for tectonic shifts.