GPS Reliability Under Threat: Researchers Warn Shipping Industry Must Prepare for Navigation Without Satellite Systems

## GPS No Longer Dependable, Researcher Warns Shipping Industry The shipping industry must urgently develop and adopt alternative navigation systems as GPS jamming and spoofing incidents continue to escalate, according to a researcher who has spent years tracking satellite navigation interference from space. Kian Bostani Nezhad, a PhD researcher based in Denmark, delivered the warning in a recent interview with *Splash247's* Maritime CEO series. Bostani Nezhad, who has developed a novel system for detecting and monitoring satellite navigation interference from orbit, said the frequency and sophistication of GPS disruption events have reached a point where the maritime industry can no longer treat satellite-based positioning as a reliable primary navigation method. 'Ships must learn to navigate without GPS,' Bostani Nezhad told Splash247, encapsulating a concern that has been growing steadily within maritime safety and regulatory circles. ### A Growing Threat at Sea GPS jamming and spoofing — where signals are either blocked or falsified to mislead receivers — have become increasingly prevalent in geopolitically sensitive regions, including the Baltic Sea, the Black Sea, the Eastern Mediterranean, and parts of the Middle East. Vessels operating in these areas have reported incidents of position errors ranging from minor discrepancies to wholesale displacement of indicated position by hundreds of kilometres. The consequences for commercial shipping are significant. Navigational errors caused by compromised GPS data can lead to grounding, collision, or entry into restricted waters — all with potentially severe safety, legal, and commercial implications. Bostani Nezhad's space-based interference detection system represents a new approach to monitoring the scale and geography of the problem, providing data that could help authorities and vessel operators better understand where and when GPS signals are at risk. ### Industry Urged to Invest in Redundancy The researcher's warning aligns with calls from maritime regulators and industry bodies for vessels to maintain robust backup navigation capabilities, including inertial navigation systems, eLoran, celestial navigation proficiency, and radar-based positioning. The International Maritime Organization (IMO) has previously acknowledged the vulnerability of GNSS systems and encouraged member states to support resilient navigation infrastructure. For shipowners and operators, the message is clear: over-reliance on a single, potentially compromised positioning system is an unacceptable operational risk in the current environment. Investment in crew training for non-GPS navigation techniques, alongside hardware redundancy, is increasingly viewed not as optional best practice but as an operational necessity. As Bostani Nezhad's research continues to shed light on the true scale of satellite interference globally, the maritime industry faces a pressing challenge to adapt its navigation culture and infrastructure before a major incident forces the issue.