According to Gard Club, this interference and jamming have resulted in loss of or inaccurate GPS signals and has affected vessels’ navigation and communication equipment.

On 24 September 2020, The US Department of Transportation’s Maritime Administration Advisories (MARAD) issued an regarding multiple instances of significant GPS interference reported worldwide in the maritime domain.

Credit: U.S. Transportation Command

Similarly, The US Coast Guard’s Navigation Center (NAVCEN) investigates reports of GPS interference by civil, non-aviation GPS users and researches these reports and, if possible, establishes the mostly likely cause.

In the majority of reported GPS interference instances in the years 2017-2019, 37 were reported by vessels operating in the Mediterranean Sea, with 22 of those reported in the vicinity of Egypt.

In addition, 2 instances were reported in the Black Sea (Odessa, Ukraine and Novorossiysk, Russia). Furthermore, there were 1 instance reported in Hodeidah, Yemen, 1 in the Strait of Hormuz and 2 in the port of Jeddah, Saudi Arabia. The reported locations are shown as red dot on the map above.

During the same period, there were also a number of instances of GPS interference reported in China; 4 in the vicinity of Shanghai in Eastern China, 1 in the vicinity of Qingdao in Eastern China, and 1 in the vicinity of the Sea of Japan.