Is the Earth’s magnetic field about to flip?
Is the Earth’s magnetic field about to flip? – As it says on the cover of venerable “Hitch Hikers Guide to the Galaxy … “DON’T PANIC” (yet). But here’s a curious thing : The strength of the Earth’s magnetic field has decreased by 10% over the last 150 years, raising the possibility that it might be about to collapse and reverse, so that the South Pole becomes the magnetic North Pole.
At the current rate of decline our magnetic field could vanish within 1500 to 2000 years before re-establishing itself with the poles reversed. However this is not a new phenomenon – the Earth has been flipping its magnetic field about every 100,000-200,000 years – but the last flip was over 800,000 years ago, so we are well overdue for it to happen again. But scientists are sceptical that it will come to that at the moment
However, (why is there always an however – sigh), over the southern Atlantic Ocean, a continued weakening of the magnetic field has diminished the shielding effect it has locally in protecting the Earth from the natural radiation that bombards our planet from space. As a result, satellites in low-Earth orbit are left vulnerable to that radiation as they pass over the region known as the South Atlantic Anomaly. Among the satellites that have fallen prey to the harmful effects was one from Denmark designed, ironically, to measure the Earth’s magnetic field. The weakening of our magnetic field may also contribute to the loss of our protective ozone layer, which shields us from cancer-causing ultraviolet rays.