Magnetic Disturbances & Anomalies
In Bermuda Triangle
It has been hypothesized that the interference of local magnetic disturbances and anomalies results into faulty reading of the compass and as a consequence ships and planes in Bermuda Triangle were misdirected and eventually were lost. Let's explore the credibility of such hypothesis.
Earth's magnetism is a commonly known phenomena to any student who has read physics. The magnetic fields produced along the earth's surface is due to the magnetic forces emanating out of the core of the earth. And this magnetic field is usually quite uniform across the surface of the earth.
However, in certain places on the earth's surface, particularly those that are rich with iron ore deposits, the magnetic field can vary substantially. For example, northern Minnesota, Lake Superior, or extensive lava beds such as that near Grants, New Mexico are such exceptions where there are some local magnetic disturbances.
In such areas where there are local variations in magnetic fields, the compass can not be relied on because it gives faulty readings due to the magnetic field interference. The aeronautical charts and even navigational charts warn the pilots of such situation. Such irregular behavior of the compass in such situations is a known fact and there is nothing strange or mysterious about it.
The Navy has conducted tests on the Bermuda Triangle area to check if there is any such magnetic disturbances in this area. They have done so as a worldwide program to update navigational charts and not to investigate any mystery in Bermuda Triangle. Their findings are very clear... there is no local magnetic disturbance in Bermuda Triangle area.
In contrast to magnetic disturbances, magnetic anomalies are small deviations in the compass which are usually caused by earth's movement and underlying ferromagnetic substances, and such small compass deviations are unlikely to cause any effect any passing boats or planes.
Oceanographer Simon Boxall mentioned that magnetic anomaly can be caused by the earth's mantle moving below the earth's crust. And the nearest such location is 1,000 miles off the coast of Brazil which is nowhere close to Bermuda Triangle.
A well known characteristic of a compass is that its needle is quite unstable and moves when subjected to rough weather. It is a common experience of any pilot that the compass needle swings when the boat or the plane tilts from side to side due to rough weather.
This is because the needle is placed on a pivot to make it frictionless and although a light oil used in the container of the compass to make the needle movement smooth, the needle still swings in such conditions due to gravity. And it doesn't require a very rough weather or turbulence to see wild swings of the compass needle. However, stronger the turbulence, wider would be the swings of the compass, and in violent weather, the needle can keep spinning.
This is a well known flaw in the ordinary compass. And that is the reason why electric or air-driven gyroscopic compasses are now used. Although they have their own problems, they remain relatively steady during rough weather or turbulence.