Worried about the magnetic North Pole sprinting towards Russia? Don't be, boffins say, it'll be back sooner or later
- Reference: 1589522467
- News link: https://www.theregister.co.uk/2020/05/15/magnetic_north_pole/
- Source link:
Unlike the fixed geographic North Pole, the magnetic North Pole shifts, and we've measured this movement since 1831. Over time, scientists discovered it was slowly meandering from the northern Canadian coast, across the Bering Strait, and towards Siberia at a rate of around 15 kilometres (9 miles) per year.
Since the 1990s, that shift has been accelerating and now moves up to 60 kilometres (37 miles) per year southwards towards Russia. You can see the rate change in the video below:
[1]Youtube Video
Now, scientists from the University of Leeds in the UK, and the Technical University of Denmark, believe they have figured out why this is happening: two blobs of iron deep under the surface moving around. They came to this conclusion after readings of our planet's magnetic field were mapped out, showing the underground iron's movement. As the European space agency put it:
Numerical models based on measurements from space, including from ESA’s [2]Swarm mission , have allowed scientists to construct global maps of the magnetic field. Tracking changes in the magnetic field can tell researchers how the iron in the core moves.
“By analysing magnetic field maps and how they change over time, we can now pinpoint that a change in the circulation pattern of [iron] flow underneath Canada has caused a patch of magnetic field at the edge of the core, deep within the Earth, to be stretched out,” [3]added Phil Livermore, co-author of a paper detailing the findings, [4]published in Nature Geoscience this month. and professor at the School of Earth and Environment at the University of Leeds.
“This has weakened the Canadian patch and resulted in the pole shifting towards Siberia.”
The magnetic north pole sits in between two large patches of molten iron, and as they tug against each other it’s moved south from the Canadian Arctic towards Siberia. Here’s a diagram of what that looks like:
[5]
Image Credit: Livermore et al and Nature Geoscience
"The patches of negative magnetic flux are both roughly the size of Canada," Livermore told The Register . "The moving pole is a local effect and the remainder of the Earth’s magnetic field hasn’t changed much."
The data shows that the magnetic north pole will continue moving south for a while. “Models of the magnetic field inside the core suggest that, at least for the next few decades, the pole will continue to drift towards Siberia,” he concluded.
“However, given that the pole’s position is governed by this delicate balance between the Canadian and Siberian patch, it would take only a small adjustment of the field within the core to send the pole back to Canada.” ®
[1] https://youtu.be/rzFtCp4g4C0?t=23
[2] https://www.theregister.co.uk/2013/11/27/swarm_satellites_in_position_to_begin_mapping_earths_magnetic_fields/
[3] http://www.esa.int/Applications/Observing_the_Earth/Swarm/Magnetic_north_and_the_elongating_blob
[4] https://www.nature.com/articles/s41561-020-0570-9
[5] https://regmedia.co.uk/2020/05/14/magnetic_north_pole.jpg
Fake news
Fake news spread by Trump to provide cover for the Russians stealing the pole.
"the geographic North Pole also moves a...bit...nutation"
Nutation (nodding) comes from the moon pulling on the earth's equatorial bulge to make the equinoxes come a bit earlier each year. It turns the pole (relative to the stars) in a cycle of about 26,000 years. The circle (among the stars) described by the pole is quite big e.g. when the pyramids were built, the pole was nowhere near the present "pole star".
But (on a longer timescale) the pole moves on the surface of the earth, too. Of course, the angular momentum of the spinning earth doesn't change much, but that doesn't say that its surface features must stay pointing the same way e.g. see this [1]demonstration on YouTube . Luckily for us, the gravitational attraction of the moon on the uneven distribution of continents keeps the pole about where it is on our familiar surface, so we don't end up (for example) with Africa at the north pole. The maths was published in 1932 ( [2]Milanković ).
[1] https://www.youtube.com/watch?v=1VPfZ_XzisU
[2] http://elibrary.matf.bg.ac.rs/handle/123456789/3675
Earth's rotatation axis with respect to a Reference Pole
is measured regularly with several techniques - see
https://www.iers.org/IERS/EN/Science/EarthRotation/EOP.html
@ Dinanziame
Sure we live on a weeble. (Not a technical term, but a child's toy)
But ask yourself... what impact does this have on climate change?
I don't think anyone has studied this to establish a correlation.
The Canadians have sold the Magnetic pole to Putin.
Niw, he has his magmanauts in unobtanium tugs deep below the earth, towing the pole to Siberia so that he can mine all the magnetism out of it.
Why have the lying, fake, mainstream media not mentioned this?
Isn't it obvious?!?
Russia sucks! And America blows!
Well boys, I reckon this is it: magnetic combat, toe to toe with the Rooskies.
"The data shows that the magnetic north pole will continue moving south for a while."
Am I missing something, but doesn't the ESA video show the magnetic north pole has moved CLOSER to the geographic north pole between 1840 and 2019, something I would struggle to describe as "moving south"?
We're also long over-due a complete polar inversion I believe. Always wondered if that was a slow (in human terms but still a blink of the eye in geological ones), progressive rotation or it would get to a point and suddenly flip overnight...
Always wondered if that was a slow (in human terms but still a blink of the eye in geological ones), progressive rotation or it would get to a point and suddenly flip overnight...
There's a wikipedia article on it which suggests that ~5000 years is a likely timescale, with large variations. Not overnight, though.
Magnetic reversals aren't terribly regular so (like volcanoes) they can't be 'overdue'. They seem to follow a broad pattern of a gradual dwindling of the global magnetic field over a few thousand years with the appearance of several local magnetic poles around the globe, followed by a flip and a gradual strengthening of the global field.
The duration of the reversal itself isn't known with huge precision, but anything between 2000 and 12000 years seems to be the best fit; although at least one paper proposes the most recent Bruhnes-Matuyama reversal about 0.781My was complete within 200 years.
https://web.archive.org/web/20100731030313/http://es.ucsc.edu/~rcoe/eart110c/Coeetal_Steens_Nature95.pdf
Though, just to make it more complex, the apparent duration of the reversal in any particular location is incredibly varied as it relies on issues such as the geomagnetic latitude and local non-dipole components of the Earth's magnetic field during the transition.
God I hated palaeomagnetism when I did my MSc - it's absolutely bloody brilliant - until it isn't. Though it was a damn sight more useful than the radioactive dates I was using which were very much 'pick a number between yesterday and a hundred million years ago' due to hydrothermal contamination. Ooops - I digress.
"Am I missing something, but doesn't the ESA video show the magnetic north pole has moved CLOSER to the geographic north pole between 1840 and 2019, something I would struggle to describe as "moving south"?"
It moved closer to the geographic pole until about 2017, and has now passed it and is moving south again, but on the opposite side. So it would be a bit misleading to say it has moved south since it's currently further north than it has been for most of recent history, but it's correct to say it is currently moving south.
it’s moved south
When you're at the geographic north pole, any way is South.
It's the Atalantians
They're preparing to open the crust to hoist a great big trash catcher into space to gather all the crap we've put up there because it's interfering with their Instagram connection with Tau Alpha Ceti.
Error West, compass best
Well that's having to be rearranged :(
Argh!
I vaguely remember the geographic North Pole also moves a tiny bit (a few meters), due to something called nutation (not a typo).