Pole Shift of Noah s Day About to Happen Again

The magnetic field protecting our planet originates deep in the Earth's core but fluctuates in strength over time. Image credit - ESA/ATG medialab

As Globe's magnetic shield fails, so practise its satellites. First, our communications satellites in the highest orbits get down. Next, astronauts in low-Earth orbit can no longer phone home. And finally, catholic rays first to bombard every human on Earth.

This is a possibility that nosotros may start to face up not in the next 1000000 years, not in the next thousand, merely in the next hundred. If Earth'due south magnetic field were to disuse significantly, it could collapse altogether and flip polarity – changing magnetic northward to south and vice versa. The consequences of this process could be dire for our planet.

Most worryingly, we may be headed correct for this scenario.

'The geomagnetic field has been decaying for the last iii,000 years,' said Dr Nicolas Thouveny from the European Centre for Enquiry and Educational activity of Environmental Geosciences (CEREGE) in Aix-en-Provence, France. 'If it continues to autumn down at this rate, in less than one millennium nosotros volition be in a critical (period).'

Dr Thouveny is ane of the chief investigators on the five-year Building project, which has been running since 2014. Together with his colleagues, he has been investigating the history of Globe's magnetic field, including when it has reversed in the past, and when it might again.

Catholic rays

Our planet's magnetic field is predominantly created by the menses of liquid iron inside the core. It has always been a feature of our planet, but it has flipped in polarity repeatedly throughout Earth's history. Each fourth dimension information technology flips – up to 100 times in the by 20 million years, while the reversal can take about 1,000 years to complete – it leaves fossilised magnetisation in rocks on Globe.

By taking cores - or columns - of sediments from the sea floor, like a long straw that can extend downward up to 300 metres with the help of a drill, we can expect back in time and see when these reversals occurred. Dr Thouveny and his squad looked at two item forms of elements that immune them to probe the history of our planet's magnetic field in greater detail.

For a polarity reversal to occur, the magnetic field needs to weaken past most xc% to a threshold level. This procedure can take thousands of years, and during this time, the lack of a protective magnetic shield around our planet allows more than cosmic rays – loftier-energy particles from elsewhere in the universe – to hitting us.

When this happens, these cosmic rays collide with more and more atoms in our atmosphere, such as nitrogen and oxygen. This produces variants of elements called cosmogenic isotopes, such as carbon-fourteen and beryllium-10, which fall to the surface. And past studying the quantities of these in cores, we can encounter when polarity reversals took place.

'The geomagnetic field has been decaying for the last 3,000 years.'

The last reversal occurred between 772,000 and 774,000 years ago. Since and then, the field has almost reversed fifteen times, chosen an excursion, dropping in forcefulness significantly simply not quite reaching the threshold needed earlier rising again. This is when nosotros are about at gamble - as the field decays and then recovers its strength. The last circuit occurred xl,000 years ago, and bear witness suggests we are heading in that direction over again.

'The geomagnetic field has been losing 30 percent of its intensity in the last 3,000 years,' said Dr Thouveny. 'From this value, nosotros predict it volition drib to near naught in a few centuries or a millennia.'

Satellites

Today, we can already see the effects of a weakened magnetic field on our satellites in orbit.

In the Atlantic Sea between South America and Africa, in that location is a vast region of Earth'southward magnetic field that is almost 3 times weaker than the field strength at the poles.

This is chosen the South Atlantic Anomaly (SAA), and information technology'south the focus of the CoreSat project being led by Professor Chris Finlay from the Technical University of Denmark (DTU) near Copenhagen. Using data from multiple satellites, including the European Space Agency's (ESA) three Swarm satellites launched in 2013, this projection is trying to figure out what is causing the SAA.

'This is a region where nosotros run into that satellites consistently (feel) electronic failures,' said Prof. Finlay. 'And we don't sympathize where this weak field region is coming from, what's producing it, and how it might modify in the futurity.'

The Earth's magnetic field has been weakening over the South Atlantic (blue region). Image credit - ESA/DTU Space

Scientists commencement noticed the SAA in the 1950s, and since then it has decreased in force by a further half dozen%, besides equally moving closer to the west. '(There) hasn't actually been any convincing explanation of it,' said Prof. Finlay, adding that scientists haven't been able to predict how information technology'southward going to alter.

The CoreSat project is hoping to change all that, using the virtually detailed data available still to study the backdrop of the magnetic field here and how it shifts over fourth dimension. By probing the SAA, the squad are hoping to see what's going on within Earth'southward core that might be causing it.

I possibility is that in that location could be a vast anticyclone in the southern portion of Globe'due south liquid metal outer core, which may be pushing out the magnetic field from the Southward Atlantic region. Another possibility is that the magnetic field in this region is pointing the wrong manner – in effect, there'due south a mini-polarity reversal taking place.

The SAA gives usa a direct expect at how a weakened magnetic field can touch satellites, as numerous spacecraft have reported electronic malfunctions when flying over this region as they are hit past catholic rays. But it's unclear at the moment if the SAA has whatever relation to the Globe'due south magnetic field flipping in polarity, which is also something Prof. Finlay and his team will investigate.

'In some simulations you lot come across features similar the SAA growing during a pole reversal,' he said. 'It's non necessarily the example, just it wouldn't be a surprise if something like this was involved in a magnetic reversal.'

A glimpse

Nevertheless, the SAA but might give u.s. a glimpse of what is to come in the nearly future. If trends continue, our planet'due south magnetic field could reverse over again in one or two millennia. Prior to that, the field may continue to weaken, and within a century nosotros could be faced with serious problems.

'The subtract in geomagnetic field is much more than important and dramatic than the reversal,' said Dr Thouveny. 'It is very important to sympathize if the present field will decay to zero in the adjacent century, because we will have to prepare.'

The research in this article was funded past the European Inquiry Council. If you liked this article, please consider sharing it on social media.

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Source: https://ec.europa.eu/research-and-innovation/en/horizon-magazine/earths-magnetic-poles-could-start-flip-what-happens-then

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