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Australia has moved five feet in 22 years and satnavs are struggling to keep up

Australia has moved so much in the last 22 years the government needs to update its latitude and longitude co-ordinates or face increasingly inaccurate GPS data.

Tectonic activity is to blame for Australia moving at a rate of 7cm (2.8 inches) per year and so an update to the country’s co-ordinates has been scheduled for January 2017. As of then, Australia will be 1.8 metres (nearly six feet) to the north of where it is officially located now.

The reason for overcompensating the distance is so that Australia should be in the exact position it should be in 2020, giving the co-ordinates a bit of breathing space. Until then, maps will remain out.

The problem with Australia moving at such a pace is the difference it creates between local co-ordinates and those of global navigation satellite systems (GNSS), which affects map information accuracy.

It helps little that the Australian Geocentric Datum of Australia (the country’s local co-ordinate system) last updated the co-ordinates in 1994, although a smartphone GPS system can be out by around 16 to 32 feet so you could, in theory, never notice the difference.

But for some navigation systems that rely on really, really accurate GPS data, such as fully autonomous vehicles, a deviation of a few feet out could mean the vehicle is on the opposite side of the road and heading into incoming traffic. Or turning into a roundabout before actually reaching it.

For some satnavs, meanwhile, the difference of five feet means it may give directions through a wall or onto a pavement, which is obviously a bad thing for drivers who lack common sense.

Dan Jaksa of Geoscience Australia told the BBC: “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.”

After 2020, Australia will switch to a new system that can account for changes over time, meaning the 2017 adjustment should be the last manual one.

“If the lines are fixed, you can put a mark in the ground, measure its co-ordinate, and it will be the same co-ordinate in 20 years. It’s the classical way of doing it. We used the old plate fixed system to make life simple, but we don’t want to do this adjustment every so often,” he added.

Australia was once connected to Antarctica and India around 100 million years ago and split up over the next 55 million years  so the movement is nothing new. Maths geeks can run the numbers on how long it will be before Australia and Asia hook up.


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