GPS monitoring stations in Japan will have to undergo comprehensive recalibration following the devastating earthquake after measurements showed that the nation’s coastline shifted by as much as 4 metres in the quake. The country’s Geonet network of approximately 1,200 GPS monitoring stations have measured a significant displacement following the quake.
Shipping maps linking GPS readings to maps – e.g. navigation to a shallow shore – would all need to be realigned as a result of the movement of the earth. For ships, the nautical charts will need revision due to changed water depths, (of about 3 feet). Much of the coastline dropped by a few feet.
- Shifting ground (bbc.co.uk)
- “Quake shifted Japan by over two meters, sped up Earthâ€™s rotation, shortened length of day” and related posts (xenophilius.wordpress.com)
- Earthquake moved Japan 8 feet over, shifted earth 4 inches (americablog.com)