Magnetic storms also interfere with flight instruments. Particularly pioneering flight instruments. While the Bermuda Triangle was once, during the 19th century, a place where a compass pointed true north with no variation, the Earth's magnetic field is constantly changing, and along with it, compass variations.
DS In regard to ships, water density needs to be considered. It is known that methane gas deposits exist below the ocean floor, and if enough gas bubbles up to the surface it can reduce water density. Just a theory.
