noun
geomagnetism; terrestrial magnetism
Scientific term for the Earth's magnetic field and related phenomena.
地磁気は地球の内部で発生している。
Geomagnetism originates from within the Earth.
地磁気の逆転は過去に何度も起きている。
Reversals of the Earth's magnetic field have occurred many times in the past.
磁気 is a broader term for magnetism in general, not limited to the Earth.
Compound of 地 (earth) and 磁気 (magnetism).