The earth’s magnetic field is the signature for life on the planet. The magnetic field is, however, not constant but is in a dynamic state of changing from time to time. Scientists have figured that the earth’s magnetic field might flip its polarity soon. Here’s how, and what that means for the planet.
The planet’s magnetic field is largely due to the spinning core in its centre. Earth behaves like an enormous bar magnet – with a north and a south pole. Over the years, scientists have observed that the magnetic field associated with the planet has not really been constant, but has been changing orientations and strengths every now and then.
To learn more about the earth’s magnetic field, scientists studied lava from the Mid-Atlantic rift, where the European and the North Atlantic tectonic plates merge. The minerals from the cooling lava serve as a record of all the magnetic changes that have happened over the span of 20 million years. Researchers have identified that the previous magnetic pole reversal happened about 780,000 years ago.
20 million years back, the earth started a cycle of switching poles every 100,000 to 200,000 years. Hence, it is not difficult to predict that a pole reversal is overdue. Scientists figuratively suggest that the switch might happen soon, but that does not mean it will happen in the near future. For the earth’s time scale, soon would mean decades or centuries together.
The earth’s magnetic north has been gradually moving towards the magnetic south over the last few decades. Researchers estimate that it is moving at a speed of 55 kilometres a year, or even faster. Adding to this, the magnetic field has lost around 10% of its strength over the last 200 years.
As opposed to many theorists, experts are sure that a pole reversal will not end life as we know it. However, there could be harsh implications. The earth’s magnetic field protects us from all harmful radiations from outer space. When the flip is underway, the magnitude of the magnetic field will reduce to one-tenth its original amount. This would mean that heavy doses of UV radiation would seep through the atmosphere, making certain places uninhabitable.
That aside, the magnetic pole switch could cause low-orbiting satellites to suffer from memory loss because of the radiations. This would lead to the failure of electric grids, causing blackouts in many parts of the world. Inevitably, this also would mean that mobile phones couldn’t be used.
Although this sounds scary, this problem can be dealt with efficiently. Satellite companies will soon start work on remedial measures for such a pole reversal.
Also, the magnetic pole flip will colour the skies with higher occurrences of the auroras. Now that is something to look forward to.