Earth’s magnetic field is acting up

[thangalin]

"Pottery jugs from between the eighth and second centuries B.C. bear administrative stamps that changed with the political situation. Unbeknown to the people firing these jugs, the act of heating locked information about the Earth's geomagnetic field into minerals present in the clay. Because the stamps provide precise information about when the pots were fired, the study allows a detailed look at geomagnetic changes over 600 years."

https://www.livescience.com/57868-earth-magnetic-field-spike...

[medius]

This is one of the most amazing things about humans to me. I marvel at how it's possible to get so much information about our universe by observing so little. Astronomy is another field that I'm really impressed with. It's possible to infer things about galaxies, stars, planets, etc. just buy observing some light coming from them to our little blue planet. Absolutely crazy.

How many such techniques we haven't even discovered or technology is not there to observe such things?

I really enjoyed reading Our Mathematical Universe by Max Tegmark that explores such things.

[ryanmercer]

Double pottery awesomeness today between that and this post https://news.ycombinator.com/item?id=18869653

[nonbel]

>"Pottery jugs from between the eighth and second centuries B.C. bear administrative stam ... the stamps provide precise information about when the pots were fired"

How do they know the dates are correct? Carbon dating doesn't work for those years: https://en.wikipedia.org/wiki/Hallstatt_plateau

[samstave]

Are these more accurate than carbon dating? Meaning - if we knew definitively that a pot was baked on a particular date - then use that as the baseline for checking another object, can we build a magnetic timeline and use it to date other things? Like bones?

[falcolas]

Oddly enough, this has a sizable impact to general aviation. Heading is typically measured using a gyro, but the heading values are calibrated to magnetic north (typically via a magnetometer or manually against a compass).

The creep of the magnetic field is noticeable in particular in the numbering of runways - they are numbered according to their heading. Some runways that have existed for a few decades are, accordingly, off by a few degrees. An older runway numbered "35" may have an actual approach heading of 340 (340 degrees from magnetic north). Not a huge problem when flying by eye, but it has the capability of causing some confusion when flying using instruments. Alternately, the runway numbers can even change.

As for GPS, this won't solve the problem either, since GPS can give you a "true" flight path using the movement over time, which with wind will not always match the actual heading of the aircraft due to wind.

[fh973]

That's why runway designations are updated periodically to reflect the magnetic change.

[theNJR]

I’m about 40 hours into Xplane 11, plus another 10 or 20 into reading and watching YouTube tutorials about GA, in particular navigation.

I now know how runways are named. Boy does that clear up a lot. Thanks :)

[souprock]

This is pretty sad. For at least decades, maybe even centuries, there have existed compasses that let you rotate the "north" indicator to match the current local magnetic declination. Adjusting as you travel is no different than the pressure adjustments that pilots make for altimeters. There is no good reason we couldn't have all of the airports using geographic north. That one is far more resistant to change, with continental drift and Earth axis wobble being far slower than magnetic pole movement.

[incompatible]

I wonder if it will affect animals that use the magnetic field to navigate. There are birds that migrate between Siberia and Australia, for example.

[danielvf]

Runway numbers roughly corresponding to heading is really just a numbering convenience and doesn’t even always happen. Many US airports are renumbering their 02/20 runways to something else to avoid pilot confusion, even though those new numbers don’t are even more off the actual heading.

[feniv]

Earth's magnetic pole has been known to switch sides in the past. https://en.wikipedia.org/wiki/Geomagnetic_reversal

"183 reversals over the last 83 million years... A brief complete reversal, known as the Laschamp event, occurred only 41,000 years ago during the last glacial period. ... Geologists first noticed that some volcanic rocks were magnetized opposite to the direction of the local Earth's field.".

[darkerside]

When this happens, does the magnetism "rotate" around the Earth, or does it fade out and fade back in reversed?

[NeedMoreTea]

I've read a number of pieces over the years that a geomagnetic reversal might be near, and there have been flips as short as a couple of hundred years. Where "near" may be in my lifetime or in the next 500 years.

So we may not know why it's moved more than model, but I don't think we should be unduly surprised.

Here's one recent piece implying a switch could be sooner rather than later: https://www.extremetech.com/extreme/192522-earths-magnetic-f...

[ams6110]

So what exactly does that mean? If I'm driving from Chicago to Milwaukee will my compass say I'm heading South?

[petre]

Mads Faurschou Knudsen and Peter Riisager, Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK. Pages 71-74.

Based on an observed correlation between the Earth's magnetic dipole moment and oxygen isotope paleo-precipitation records from caves in Oman and southern China, Knudsen and Riisager suggest that the Earth's magnetic field may have influenced the amount of rainfall in low-latitude regions during the past 5000 years. The physical mechanism that underpins the geomagnetic-climate link is provided by the cosmic-ray-climate theory, which suggests that galactic cosmic ray (GCR) particles entering the atmosphere influence the formation of low-altitude clouds and, in turn, climate. The geomagnetic field shields the Earth from GCR particles and, according to the cosmic-ray-climate theory, it therefore has the potential to influence cloud formation, rainfall, and climate. Since the amount of GCR particles entering the atmosphere is also modulated by the Sun, the cosmic-ray-climate theory is central to the ongoing scientific debate regarding the role of the Sun in climate change. Knudsen and Riisager lend support to the notion that variations in the Earth's magnetic field may influence the climate of our planet. They also deliver independent support for certain aspects of the cosmic-ray-climate theory.

https://www.eurekalert.org/pub_releases/2009-01/gsoa-jgm0108...

[chiefalchemist]

> "On 15 January, they are set to update the World Magnetic Model, which describes the planet’s magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones."

Boggles the mind to think that Mother Nature is the foundation for such significant technology.

If only the Twilight Zone was still around to do an episode on the magnetic north suddenly going MIA. It has gone south (literally) a couple times I believe.

[vanattab]

"Boggles the mind to think that Mother Nature is the foundation for such significant technology."

As best I can tell Mother Nature is the foundation of ALL technology...

[lostmsu]

On the picture, the movement of the pole slightly resembles a pendulum: it is slow at the beginning far from the geographic pole, and it speeding up as it nears it. Makes perfect sense, actually.

[exabrial]

Being a son of a geologist, I found it fascinating we could tell from geologic history how many times the earth's magnetic field has flipped. Turns out we're long overdue for a reversal.

[ComputerGuru]

> Update, 9 January: The release of the World Magnetic Model has been postponed to 30 January due to the ongoing US government shutdown.

This article isn't much without the accompanying model.

[peterwwillis]

Since the US is on extended winter vacation, maybe China or Russia can maintain the world magnetic model?

[golemotron]

It was foretold: https://www.imdb.com/title/tt0298814/

[phkahler]

>> In 2018, the pole crossed the International Date Line into the Eastern Hemisphere. It is currently making a beeline for Siberia.

I knew Putin was a super villain. Now he's stealing the north pole!

[olivermarks]

Article linked is truncated, last sentences lifted from here https://www.nature.com/articles/d41586-019-00007-1?utm_sourc...

[NeedMoreTea]

That's a much better article, free of claims of scientific bafflement. :)

[sctb]

Thanks! We've updated the submission from https://www.newsweek.com/earth-magnetic-field-baffle-scienti..., which points to this.

[blurbleblurble]

So it begins