London:Scientists using simulations in the lab have revealed that changes in the direction of the Earth's magnetic field may take place 10 times faster than previously thought.
The study, published in the journal Nature Communications, gives new insight into the swirling flow of iron 2,800 km below the planet's surface and how it has influenced the movement of the magnetic field during the past hundred thousand years.
"We have very incomplete knowledge of our magnetic field 400 years ago. Since these rapid changes represent some of the more extreme behaviour of the liquid core, they could give important information about the behaviour of Earth's deep interior," said study researcher Chris Davies from the University of Leeds in the UK.
According to the researchers, our magnetic field is generated and maintained by a convective flow of molten metal that forms the Earth's outer core. The magnetic field is constantly changing.
Satellites now provide new means to measure and track its current shifts but the field existed long before the invention of human-made recording devices.
Read |13 UK universities face insolvency without bailout
To capture the evolution of the field back through geological time scientists analyse the magnetic fields recorded by sediments, lava flows and human-made artifacts.
Accurately tracking the signal from Earth's core field is extremely challenging and so the rates of field change estimated by these types of analysis are still debated.
For the current findings, the research team combined computer simulations of the field generation process with a recently published reconstruction of time variations in Earth's magnetic field spanning the last 1,00,000 years.