The global magnetic field is Changing
The global magnetic field has weakened 10% since the 19th century.
A new study by the European Space Agency’s constellation of Swarm satellites reveals that changes may be happening even faster than previously thought. In this map, blue depicts where Earth’s magnetic field is weak and red shows regions where it is strong.
Earth’s magnetic field protects us from solar storms and cosmic rays. Less magnetism means more radiation can penetrate our planet’s atmosphere.
Indeed, high altitude balloons launched by Spaceweather.com routinely detect increasing levels of cosmic rays over California. Perhaps the ebbing magnetic field over North America contributes to that trend.
As remarkable as these changes sound, they’re mild compared to what Earth’s magnetic field has done in the past.
Sometimes the field completely flips, with north and the south poles swapping places. Such reversals, recorded in the magnetism of ancient rocks, are unpredictable.
They come at irregular intervals averaging about 300,000 years; the last one was 780,000 years ago. Are we overdue for another? No one knows.
TO BE CONTINUED ON