By David Hambling
Ships around the world are reporting false locations, seeming to circle Point Reyes near San Francisco when they are actually thousands of kilometres away.
The locations are broadcast by each ship’s Automatic Identification System (AIS). These are required under international law to signal a vessel’s identity and GPS location. Bjorn Bergman of the environmental watchdogs SkyTruth and Global Fishing Watch discovered the anomalies from a historical database of AIS information.
Bergman was tipped off when he noticed records from 2018 and 2019 of satellites …