Here's why:
* Magnetic Poles vs. Geographic Poles: The Earth's magnetic field is generated by the movement of molten iron in the Earth's core. This field isn't perfectly aligned with the Earth's rotational axis (which defines the geographic poles). The points where the magnetic field lines are vertical are called the magnetic poles.
* Variation at the Poles: At the magnetic poles, the magnetic field lines are nearly vertical, meaning the magnetic compass needle will point almost straight down. This creates a large difference between the direction the compass points (magnetic north) and the direction of true north (geographic north), resulting in the greatest magnetic variation.
Key Points:
* The magnetic poles are not fixed locations and can shift over time.
* The greatest magnetic variation can be found near the magnetic north pole and the magnetic south pole.
* Magnetic variation is not the same as magnetic inclination, which is the angle between the magnetic field lines and the horizontal.
It's important to note that magnetic variation can change depending on your location on Earth. If you're using a compass for navigation, it's crucial to account for this variation to ensure accurate directions.
