KOMPAS.com- About 42,000 years ago, something extraordinary happened on this planet. Earth’s magnetic field upside down.
For a while the north magnetic field is south and the south magnetic field is north.
This reversal of the magnetic field has a very damaging effect extreme weather and possibly caused the major extinctions of mammals and Neanderthals.
As quoted from New Scientist, Monday (22/2/2021) these results were obtained after researchers conducted an analysis of fossilized tree rings.
As known Earth’s magnetic field extends into outer space and is most concentrated in the north and south poles.
Sometimes the magnetic field does reverse every 200,000 to 300,000 years, but we have very little evidence of how that impacts planet Earth.
Now through a study, finally Alan Cooper from the South Australian Museum in Adelaide, Australia, along with his colleagues managed to find some answers about the mystery of the Earth’s magnetic field which was reversed 42,000 years ago.
The team performed radiocarbon analysis on ancient kauri tree rings (Agathis australis) which was preserved to study the most recent reversal of the magnetic field on Earth called Laschamp.
“The tree lived through the Laschamps incident. And to detect exactly when the magnetic field was reversed we used radiocarbon and carbon-14 shifts,” explains Cooper.
Earth’s magnetosphere or the area around the planet which is dominated by Earth’s magnetic field weakens when the magnetic poles are reversed.
Cooper and his team estimated that during the Laschamp event, about 42,000 years ago, Earth’s magnetic field strength was only about 6 percent of the current magnetic field level.