The collapsing magnetic field of the Earth — a rare, but not a single case in its history, which people are very afraid, because of the catastrophic consequences for all life on the planet.
Associate Professor Bradford Clement of Florida International University in Miami published his findings on the subject in the journal Nature for April 8.
Changing the polarity of the magnetic field of the Earth is a very long but unpredictable intervals, the most recent of which was about 790,000 years ago.
Then the compass needle pointing to the south, not north.
Change of poles occurs when there is a change in the movement of the mantle beneath the Earth's crust. Slowly moving around an iron core in the center of the planet, it creates a dynamo effect, which forms a magnetic field.
The intensity of the slow movements of the mantle for a while before changing the rhythm, and then there is a new polarity.
But this process is not lightning fast as it seems. It is very durable and can take anywhere from a few thousand to 28,000 years.
Analysis old rocks shows such ranges where the magnetic field in the world was not. They contain a residual magnetic echo from the magnetic field that existed at the time.
On average, the change of poles take about 7000 years.
And this change of polarity is not immediately cover the entire planet. First is to install small mini magnetic fields around the equator, and then, with the expansion of the movement's mantle in high latitudes, there will be and the total magnetic field of the planet.
Calculations Clement show that 2000 years later the equator will be protected by a mini magnetic fields, and only about 10,000 through the magnetic field and cover the pole.
The reason for this, said Clement, in different speeds of the mantle beneath the Earth's crust. It moves faster at the equator than at the poles.
Ultimately the two main poles will be set again, but with opposite polarity.
No one knows what would happen to life on Earth if there would be a change of poles today, but simulation shows that the apocalypse will come for us.
The problems with our dependence on the orientation of the magnetic field to navigate, seem flowers compared with the problems that arise with the loss of an external "magnetic shield" of the planet. It protects all life from the solar radiation. Without it, the solar wind plasma from solar flares will reach the upper atmosphere, heating it and causing catastrophic climate change.
French professor of geophysics Gauthier Hulot in 2002 has raised a panic to find the weakening of the magnetic field of the Earth around the poles, which can be interpreted as an early sign of change near the poles.
It could happen tomorrow and through tens of millions of years.
The shortest interval between polarity reversal was recorded in the 20,000-30,000 years, and the longest — 50 million years old.
However, life on the planet as there was, and there are at present, moving is not a polarity reversal. Consequently, the death of all living things will not bring this disaster, but the mass extinction of plants and animals as well as humans will be provided.