What are geomagnetic spikes and what are the prospects and implications of another one coming along?
The Earth has a powerful magnetic field. Credit: NASA
The Earth’s magnetic field, generated some 3,000 km below our feet in the liquid iron core, threads through the whole planet and far into space – protecting life and satellites from harmful radiation from the sun. But this shielding effect is far from constant, as the field strength varies significantly in both space and time.
Over the last century, the field strength has changed relatively slowly: the biggest change is a 10% fall in the southern Atlantic, which is still a large enough effect to cause electronic problems for satellites that have passed through the region. However, new observations and modelling suggest that a much greater change strangely occurred around 1000 BC in a much smaller region.
This “geomagnetic spike” offers a potentially profound new insight into the dynamics and evolution of Earth’s hidden interior that is now starting to be uncovered.
So what are geomagnetic spikes and what are the prospects and implications of another one coming along? The geomagnetic spike of 1000 BC was first identified from copper slag heaps located in Jordan ...