The problem is that local coordinates, used to produce maps and measurements, and global navigation satellite systems differ by more than one meter. This may not seem like much but it currently causes delays, causes people to get lost, and is less energy efficient.
Explaining one of the problems, 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.”
To resolve the problem, Australia will shift its longitude and latitude. Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth’s surface; whereas latitude is a geographic coordinate that specifies the north–south position of a point on the Earth’s surface.
The problem exists because satellite systems give location data based on global lines of longitude and latitude, these are always stable even if the continents on Earth shift. The continent that is currently shifting the most is Australia. Here the land mass is moving about 7 centimeters north each year. This geographic shift is due to tectonic movements (plate tectonics is the theory that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core.)
A related reason for making the change is to assist with the development of self-driving cars; these controversial vehicles require accurate location data to navigate. Physicist NanoPaleoMagnetism (@NanoPaleoMag) tweeted: “Interesting implication of plate tectonics in age of driverless cars: need to continuously update map coordinates…”
As to the solution, ABC News reports that on January 1, 2017, Australia’s local co-ordinates will also be shifted further north by 1.8 meters. This is an over-correction, designed to allow Australia’s local co-ordinates and the Earth’s global co-ordinates to align in 2020.
