The International Real-time Magnetic Observatory Network, with over 100 interlinked geomagnetic observatories around the world, has been recording the Earth's magnetic field since 1991.
國際實時磁場觀測站網絡由遍佈全球的一百多座地磁場觀測站所組成，自1991年起一直保持對地磁場的監察。