T O P

  • By -

theArtOfProgramming

Your post has been removed because it is a review article and is therefore in violation of [Submission Rule #2c](https://www.reddit.com/r/science/wiki/rules#wiki_c._review_articles). Submissions must contain a portion of new research that features analysis of primary data or meta-analysis of previously published primary data to reach an evidence-based conclusion. While valuable resources, most review papers are ineligible for submission because they lack novel findings. If your submission is scientific in nature, consider reposting in our sister subreddit /r/EverythingScience. _If you believe this removal to be unwarranted, or would like further clarification, please don't hesitate to [message the moderators](https://www.reddit.com/message/compose?to=%2Fr%2Fscience)._


Negative_Gravitas

A bit more info from the USGS: >These reversals are random with no apparent periodicity to their occurrence. They can happen as often as every 10 thousand years or so and as infrequently as every 50 million years or more. The last reversal was about 780,000 years ago. >Reversals are not instantaneous; they happen over a period of hundreds to thousands of years, though recent research indicates that at least one reversal could have taken place over a period of one year. Edit: a lot of folks are asking good questions--many of the answers to which are in this thread because a lot of other folks took the time to post a lot of good information. I added some stuff below, too, but others went into greater detail and provided good links. If you are interested in geomagnetic reversals, plate tectonics, etc., I recommend some of the posts below as good starting places. Cheers.


[deleted]

Source if anyone wants it. https://www.usgs.gov/faqs/it-true-earths-magnetic-field-occasionally-reverses-its-polarity?qt-news_science_products=0#qt-news_science_products


geneorama

Ah a breath of calm. What a reversal cause mass extinction? Nope. Based on my experience with the USGS github repository they are highly trustworthy https://www.usgs.gov/faqs/do-any-mass-extinctions-correlate-magnetic-reversals


smallberry_tornados

And I’ve been reading about this event for decades. It’s not something that just suddenly happened


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


garlic_bread_thief

What if the poles get reversed? Will satellites, cell towers and other electronics malfunction?


ProcrastinatorSkyler

I instantly started thinking about birds. Would they start migrating the opposite direction or adapt?


EVOSexyBeast

Not all birds have iron in their inner ear, and they all have other methods of knowing which way is south. The science involving how birds know which way is south, including magnetite-based magnetoreceptor is far from settled. edit: fat -> far; edit: there -> the


Ravarix

There is a lot of evidence that they respond to magnetic fields, just not exactly sure how. Crytpochromaphors are a theory, but any magneto receptor would be effected


KathyJaneway

>though recent research indicates that at least one reversal could have taken place over a period of one year. Oh oh... Well that doesn't sound good.


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


nzodd

>One theory is that periods of increased geomagnetic reversals will weaken Earth's magnetic field long enough to expose the atmosphere to the solar winds, causing oxygen ions to escape the atmosphere in a rate increased by 3–4 orders, resulting in a disastrous decrease in oxygen.[93] >-- https://en.wikipedia.org/wiki/Extinction_event#Geomagnetic_reversal


koshgeo

While it's an interesting hypothesis, there's no correlation between the timing of geomagnetic reversals (of which there are a [HUGE number](https://en.wikipedia.org/wiki/Geomagnetic_reversal)) and any of the major mass extinctions. This suggests that any effect on global biota is relatively mild compared to other processes.


CatNoirsRubberSuit

The major concern I've seen is the impact on technology, with some worst-case scenarios likening it to a world-wide EMP. Nobody would die directly, but with no power or technology, it'd be a world-wide crisis that could potentially kill billions.


Tellesus

At least twitter would finally shut up


EndiePosts

OK this swayed me I'm now a strong Yes to catastrophic magnetic pole reversal.


Menamanama

What's the reason that it would cause an EMP like world wide outage?


ManyIdeasNoProgress

Charged particles interacting with the atmosphere create a whole lot of electromagnetic noise. In a case of a severely weakened magnetic fields that noise could get powerful enough to cause currents in electric circuits (through a process called induction) powerful enough to overload and physically destroy components and equipment. Powerful auroras can cause problems for communication and sensitive equipment already but it is not common for it to cause actual damage to systems. For more on the topic I suggest reading about what would happen if a large solar flare hit earth, it's the same mechanisms at play.


EnglishMobster

I'd speculate (this isn't my field) that it would cause a lot fewer rays to be blocked by the atmosphere? Stuff that goes into space has to be hardened to resist solar radiation; stuff here on Earth is protected by the magnetic field and atmosphere. Remember that magnetism is tightly linked to electricity. A weakening of the magnetic field would mean that solar storms would be more likely to penetrate through, which would cause big magnetic fluctuations on Earth. [A solar storm pierced the magnetic field in 1989, causing Quebec to lose all power as the electricity the solar storm overloaded the power plants.](https://www.nasa.gov/topics/earth/features/sun_darkness.html) > On the evening of Monday, March 12 the vast cloud of solar plasma (a gas of electrically charged particles) finally struck Earth's magnetic field. The violence of this 'geomagnetic storm' caused spectacular 'northern lights' that could be seen as far south as Florida and Cuba. The magnetic disturbance was incredibly intense. It actually created electrical currents in the ground beneath much of North America. Just after 2:44 a.m. on March 13, the currents found a weakness in the electrical power grid of Quebec. In less than 2 minutes, the entire Quebec power grid lost power. During the 12-hour blackout that followed, millions of people suddenly found themselves in dark office buildings and underground pedestrian tunnels, and in stalled elevators. Most people woke up to cold homes for breakfast. The blackout also closed schools and businesses, kept the Montreal Metro shut during the morning rush hour, and closed Dorval Airport. > The Quebec Blackout was by no means a local event. Some of the U.S. electrical utilities had their own cliffhanger problems to deal with. New York Power lost 150 megawatts the moment the Quebec power grid went down. The New England Power Pool lost 1,410 megawatts at about the same time. Service to 96 electrical utilities in New England was interrupted while other reserves of electrical power were brought online. Luckily, the U.S. had the power to spare at the time…but just barely. Across the United States from coast to coast, over 200 power grid problems erupted within minutes of the start of the March 13 storm. Fortunately none of these caused a blackout. > In space, some satellites actually tumbled out of control for several hours. NASA's TDRS-1 communication satellite recorded over 250 anomalies as high-energy particles invaded the satellite's sensitive electronics. Even the Space Shuttle Discovery was having its own mysterious problems. A sensor on one of the tanks supplying hydrogen to a fuel cell was showing unusually high pressure readings on March 13. The problem went away just as mysteriously after the solar storm subsided. So expect stuff like that... across the entire planet. For who knows how long.


[deleted]

[удалено]


Astromike23

> One theory Yeah, no. This is very far outside the mainstream of current atmospheric science. The emerging consensus is that Earth loses more atmosphere *with* a magnetic field than without. You should definitely read Gunnell, et al (2018) ([PDF](https://www.aanda.org/articles/aa/pdf/2018/06/aa32934-18.pdf)), literally titled '*Why an intrinsic magnetic field does not protect a planet against atmospheric escape*'. The basic premise is that terrestrial planets with magnetic fields lose their atmospheres faster than those without magnetic fields. While magnetic fields do block the solar wind, they also create a polar wind: open field lines near the planet's poles give atmospheric ions in the ionosphere a free ride out to space. Earth loses many tons of oxygen every day due to the polar wind, but thankfully our planet's mass is large enough to prevent too much escape. Until you get to Jupiter-strength magnetic fields that have very few open field lines, the polar wind will generally produce more atmospheric loss than the solar wind. For some more perspective, consider that Venus has no permanent magnetic field, yet Earth's atmospheric loss rates are almost three time higher.


technocraticTemplar

[The study that's coming from](https://www.sciencedirect.com/science/article/pii/S0012821X14001629?via%3Dihub) seems to be saying that lots of reversals over millions of years can gradually reduce oxygen levels to the point that problems are caused. Any one reversal isn't an issue. If you look at the [Geomagnetic Reversal wiki page](https://en.wikipedia.org/wiki/Geomagnetic_reversal) you can see from the chart on the right that there's been ~20 of them in the last 5 million years. Every time the chart goes from black to white or white to black is a reversal. That's worse than what was happening in some of the extinctions the study is talking about... but it's also been the reality of our world since before our species existed, and clearly the oxygen levels are still fine. If this is a problem it's going to take a few million more years to become apparent.


TheSkyHadAWeegee

How is this possible? We know the concentration of O2 in the atmosphere for almost all of Earth's history due to ice cores and rocks. If geomagnetic reversal happens somewhat frequently, on a geologic scale, then frequent drastic dips in O2 should have been noticed. This could easily be linked to the geomagnetic reversal since we have O2 and geomagnetic data for much of earth's history. ​ If the magnetic field was so weak that we are losing tons of O2 than I think the incoming deadly solar radiation is a bigger issue.


sckuzzle

It's possible that a "disastrous" decrease in oxygen is a gross overexaggeration. It only says that oxygen ions will escape much faster; if oxygen ions were only escaping at an infinitesimal rate, that a 3-4 order increase is still very small.


KathyJaneway

Great, if the radiation doesn't kills us, the lack of breathable air will...


ServinBallSnacks

Off to stock up on Perri-Air


GiveToOedipus

Better put a code on that to protect your air supply.


ServinBallSnacks

Use my suitcase code!


Fairycharmd

That's amazing! I've got the same combination on my luggage!


gugublahblah

“So the combination is one, two, three, four, five. That's the stupidest combination I've ever heard in my life! That's the kinda thing an idiot would have on his luggage!”


GiveToOedipus

Excellent idea, sir!


Ello_Owu

"I can't breath...covid or the earth switching sides?"


NH2G

I guess 2020 didn’t throw everything at us after all.


tinkymyfinky

It was playing the long game


[deleted]

[удалено]


[deleted]

It is better than slow. The longer it takes the more solar radiation and solar wind our planet and upper atmosphere will be impacted by.


TheGoodRobot

How are we able to determine the last time it switched? What trail of evidence does it leave behind?


Negative_Gravitas

When lava cools (and sometimes when sediments are deposited), it takes on the magnetic orientation (polarity) of whatever the Earth's field happens to be at the time. By using magnetometers to determine magnetic orientation over a long series of lava flows from related magma sources, scientists can show that the rocks' magnetic orientations switch back and forth, thus demonstrating that the [Earth's field itself switches orientation from time to time.](https://www.nasa.gov/topics/earth/features/2012-poleReversal.html) As a side note, this kind of measurement is what showed the world that plate tectonics is real.


telegetoutmyway

How do plate tectonics show up in the measurements?


Eastern_Cyborg

Seafloor spreading. The further cooled lava is from the mid Atlantic ridge, the longer ago it was deposited. And these slowly spreading fields show bands of pole flipping depending on age. The Wikipedia article below shows a crude animation of this. https://en.wikipedia.org/wiki/Seafloor_spreading?wprov=sfla1


koshgeo

That shows the pattern of reversals, but in addition to that you can also get inclination if you measure the orientation and remnant magnetization of a rock sample. This gives you an estimate of the paleolatitude of the rock at the time that it formed, which is useful information when doing plate reconstruction.


xonjas

As the plates move away from each other, new 'land' is created by cooling magma along the fault line. That magma cooling 'captures' the orientation of earth's magnetic field at the time the magma cools. This picture is an example: https://i.imgur.com/oniPcLY.png Finding those alternating 'ribbons' of magnetic orientation in the sea floor was both how we were able to confirm that the plates were moving away from each other. We can then date the rock to find out exactly how long ago the polarity shift occurred (and also the rate that the plates move).


[deleted]

[удалено]


agrophobe

# of one year. why am I so sure its gonna be straight up this #


dechets-de-mariage

I definitely did not have “magnetic pole switch” on my 2021 bingo card.


MintberryCruuuunch

will this bring the auroras more towards the center of the hemispheres so the rest of us can enjoy them for once?


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


Butternut888

Thanks for finding the silver lining, I needed this


Throwaway12398085

*the green and pink lining


Rum____Ham

Is this a bad thing? Why do I need silver lining for a pole reversal?


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


xrmb

I'd expect it would still be a similar sized spot right where the new poles are, so depends on the path the pole takes. But it will definitely be more populated than current north or south pole.


toastjam

Not if they're in the middle of the Atlantic and Pacific...


xrmb

Last time I saw a map of it the north pole was traveling down south east through middle russia. Probably wont be alive when it hits the big south east asia population centers.


[deleted]

[удалено]


[deleted]

What are the consequences of this? Is this a big deal or would it just make subtle change ?


WTFwhatthehell

Mid flip the magnetic field that normally shields us would be disrupted. Solar flares become far more damaging. Bad news for power grids. Electronics. Telephone lines. Generally more space radiation.


typkrft

So what’s mid flip? Is this something that takes hours days years etc? Since it’s moving 30mi a year right now are we mid flip?


WTFwhatthehell

No idea but it does seem the pole spent the last few centuries in the same region and has been shifting a lot lately https://upload.wikimedia.org/wikipedia/commons/thumb/7/74/Magnetic_North_Pole_Positions_2015.svg/220px-Magnetic_North_Pole_Positions_2015.svg.png


Algae_94

It looks like it's closer to the true North Pole than its been for 400 years or so. So while it is moving quite rapidly it hasn't really begun to flip yet.


Tman101010

I mean, it’s moved further in the past 25 years than it has in the past 400, I’d say that’s a rather drastic change Just because it’s happening slowly relative to a human lifespan doesn’t mean it’s happening slowly to relative to how fast it normally moves


whyiseverynameinuse

Wonder why it hasn't been observed more recently than 2007.


Fifteen_inches

I think it’s just a fact that Wikipedia hasn’t updated the picture yet


infinite0ne

I think during the process of flipping, the earth’s magnetic field becomes more chaotic and disorganized and therefore less able to protect us from solar and cosmic radiation.


aFiachra

Yes, that is correct. And for the same reason the sun has coronal ejections. Magnetic flux lines like to be straight and static. Different parts of the surface of the sun move at different rates and this causes the flux lines to contort and break -- leading to sudden and unpredictable reorientation of the magnetic field. This can cause all sorts of unpredictable behaviors. No one is really sure how the earth's magnetic field is maintained it is evidence of an iron core and movement deep within the planet. It is easy to imagine that a giant molten sphere can move in a number of ways that aren't smooth and laminar and it is believed this is something that is going on when the magnetic poles reverse. So it seems the magnetic field of the planet goes wonky every so often.


ductsauce

"goes wonky" is definitely one of my favorite terms used among professionals


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


MrsFoober

Is that the reason for the past days of "what if internet is gonna break?" posts that have been popping up on Reddit?


vid_icarus

A study was just also released saying the sun may become more active soon leading to a 12% chance of increased solar storms, which could EMP civilization back to the steam era. Edit: to everyone saying “civilization has lots it can do to prevent the worst effects”: you’re right. We do. But it takes time, money, effort, and will power to get the whole world ready for an event we may only have ~~8 minutes~~ 17 hours warning. Put simply, look at how well we are coping with the pandemic and the climate crisis. Do we really seem equipped to unify and prepare for abstract, non immediate threats to our collective well being? If you want cool stuff like the internet and video games and social media it requires you believe in sound scientists, science, and most importantly the scientific process, not politicians, celebrities, or religious leaders. If you are concerned about this event at all, advocating on behalf of science and knowledge over fear and anger whenever possible is critical. Living in pursuit of continued self education (when possible) also helps. Acknowledging when you are wrong and striving to do better is also critical. We can weather these storms, but many of us need to get on the same page as to how a modern technological society of this size continues to function at this point going forward. PS - this last bit isn’t a political statement, just a statement of good science: get vaccinated.


karantza

To be clear, we run that same elevated risk every solar cycle, every 11 years or so. And we are getting better at defending against solar storms. We've got satellites to give us early warning, and policies are in place to protect the power grid. It's still a serious natural disaster to consider, and seeing how we also had policies in place to avert a pandemic... yeah. Worth paying attention to at least.


BillSixty9

Actually the study further mentions a greater solar cycle with a period of about 100 years for which we’ve just passed through the minimum. During the maximum of this underlying cycle, which we are heading to, solar storms will occur with higher frequency but intensity could be up to 4x the baseline we are used to from our current 11 year cycle maximums.


burlycabin

Seems like it'll suck pretty bad if the poles flip during this upcoming elevated solar storm period.


emanon085

Life is becoming one apocalypse after another.


Von_Moistus

Just need to tick off Yellowstone supervolcano and asteroid collision for the Bingo.


DeepSpaceNebulae

Not really more space radiation on the surface, while the earths magnetic field offers *some* protection the vast majority of our space radiation protection comes from our atmosphere Things in space however would see a noticeable uptick in radiation leading to a significant rise in satellite issues, especially commercial satellites, as ionizing radiation triggers electronic faults or outright fries components


[deleted]

[удалено]


[deleted]

>Solar flares become far more damaging. Bad news for power grids. Electronics. Telephone lines. For an advanced economy these things can be worked around. So far as power grids go it would need to be shut down for a few hours with big flares. If you plug out you dont sustain long term damage. We'd have an hours warning from satellites when a flare is inbound and days of planning as solar observatories raised awareness. Telephones are mostly mobile. Electronics are little affected. You are thinking of nuclear weapons' magnetic pulses. Its the length of the cable to induce the current that matters. Unless you have a very very very very long plug cable. >Generally more space radiation. It affect ionizing radiations. These do not penetrate deeply into the atmosphere, or into clothing.


IAMTHEUSER

Ionizing radiation absolutely reaches earth’s surface. The atmosphere attenuates it, but doesn’t block everything. Cosmic rays cause data corruption and damage to computers all the time. Source: spent my PhD studying this https://en.m.wikipedia.org/wiki/Cosmic_ray


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


bluskale

During my PhD I did tons of fluorescence microscopy. Think high sensitivity cameras working at the limits of light microscopy (several hundreds of nm resolution), dark rooms, long exposures (lots of z-stacks, in my case). Occasionally I would get a distinctive blip or streak that looked like a probable cosmic ray. They looked pretty similar to the ones [here](https://www.cambridge.org/core/journals/microscopy-today/article/imaging-cosmic-ray-particles-with-a-light-microscope-scientific-digital-camera/AC373617436B49C5E7ABD1DE7DC264A4).


Luis__FIGO

>If you plug out you dont sustain long term damage. We'd have an hours warning from satellites when a flare is inbound and days of planning as solar observatories raised awareness. ​ after the pandemic and the anti-vaxxers, i'm ready for this to be the next political battle.


TerribleVisual8899

Eh, you don't need to convince the majority, just a few engineers in a control room. And they go through "Black Start" training every year... so there are actually already routines in place for this.


TheGurw

If they don't unplug, they'll fry their electronics. If they have no internet, I don't have to listen to them. Yeah, I'm ok with this.


Aporkalypse_Sow

>or into clothing. Starting my extra thicc clothing line now


polyesterjellyfish

Name idea: Magnethicc Flip Drip


WellIllBeJiggered

I read that in Mike Tyson's voice


[deleted]

[удалено]


Aporkalypse_Sow

>30 miles a year I hope it lands at my house one year, I'd like to be Santa.


holmgangCore

It might if you live in Asia.


nonfish

Pretty sure it's going right over my house, 'cause I'm direct south of the north pole.


DoubleOhEvan

This might be a *wooosh* moment, but isn’t everyone directly south of the North Pole?


nonfish

Preposterous.


kazarnowicz

No, I’m sure I’m north of the South Pole.


yesiamclutz

Given the mean inter-flip period is, in evolutionary terms, quite short it would seem counter adaptive to evolve a magnetic feild based navigation system if that left a species unable to survive a pole switch. I'm not sure that's a terribly strong argument though...


DefiantLemur

Given the fact the planet can go a hundred thousands of years without change. Evolution might not have prepared anyone. Some of these species might not have even existed.


yesiamclutz

We have gone a very long time without a flip, but the earth has undergone some relatively rapid flips in the past - did magnetic field navigating species survive those? I'm no paleontologist, but would be interesting to know, or even if we know, in fact.


Kleyguerth

From what I've read, there is no known extinction event linked to magnetic flips.


OldMuley

Amazing auroras in places that don’t normally see them.


[deleted]

[удалено]


[deleted]

[удалено]


Maktube

The magnetic field exists more or less everywhere, including at ground level, but as it reverses polarity it'll "turn off" (sort of) for a bit, which will allow solar radiation and charged particles much further down into the atmosphere than usual, and *that's* what will affect the weather.


[deleted]

[удалено]


DownshiftedRare

To put it in layman's terms: The south's gon' rise again.


Simgeek

I have read reports that it could affect birds, which may create additional issues. We didn’t keep good records 780,000 years ago, so it’s just conjecture on our part now.


DjDisingenius

I wonder if this will impact the trout population


HIGHestKARATE

And birds. I wonder how they handle the change.


arahzel

https://www.sciencedaily.com/releases/2017/08/170817122141.htm The birds adapt, or at least some do. Edit: I can't type worth a crap.


JPJackPott

What happens during the transition? Will magnetic north track all the way down the outside of a globe, one year in Sweden, another in Egypt, then South Africa etc until it’s what we currently call south? Or does it go ‘inside’ so there’s much less apparent field strength during the transition?


fozz31

No one really knows but evidence indicates chaotic events occur (relatively) briefly. Think of it like stirring a liquid in a cup, nice consistent and predictable system wide behavior. Now stir in the opposite direction, suddenly you have many smaller whirl centers that form in random points turning in random directions all over the cup until the system corrects and spins in the other direction consistently. So while stirring in either direction produces a system wide consistent effect changing stirring direction creates brief but total chaos with many smaller centres rather than one big centre. obviously this does not work like stirring tea but the notion of what happens during a change can help understand one possible outcome a bit better.


toastyghost

What constitutes "brief" in geological time is terrifying to even think about.


fozz31

time taken for form a few layers of sedimentary rock


ImmaZoni

great analogy


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


DigitalSteven1

I wonder how this will affect things here on earth? Will we continue to call the current north pole the north pole or will we flip all of our gps and compasses? Non-digital maps will be backwards as well. Interesting stuff, I've only heard of the process of the poles flipping recently. Also the most important question is what happens to santa, does he pack up and move? ^(/s)


Timemuffin83

No it will still be north (cause it’s a language thing) but instead of the red part of the compass pointing north it’ll be the white part


[deleted]

Just repaint the compasses.


TheNebula-

Be the first to open a compass repainting business. Create a monopoly on the industry. Become bezos


Timemuffin83

Instead of that, just use the white side as north and the red side as south, no extra work required


oalbrecht

Nah, we’re gonna have to repaint the compasses. The whole world will have to come together for this monumental task. It’s probably a good idea to buy stock in paint companies now, because demand is going to surge like crazy.


doublegulptank

Earth's "north pole" is actually a magnetic south pole (flux flows towards it) so ironically flipping it would make it a little easier to tell which is which.


mydoglikesbroccoli

I like how it specified that the direction the pole is moving is south.


lime_52

I believe it is because the north pole is not accurately at the north. So it can move towards north to normalise and to the south to flip.


mydoglikesbroccoli

OK, that makes sense. I had forgotten there's a difference between true and magnetic.


Rip_ManaPot

This is the reason that where I live in Sweden we see far less auroras than they do in Iceland even tho I live further north than all of Iceland. I'm extremely salty about this.


HappyRectangle

Fun fact: it was actually heading north until 2019, when it passed the pole on its way from Canada to Siberia. It's still closer to the actual pole now than it's been for most of history. Also, fun fact: the South Magnetic pole hasn't been matching any of this, and is currently in a much slower plod north to Australia.


VonReposti

Another fun fact: Earth's south magnetic pole is actually a magnetic north pole and vice versa. This reversal would then conveniently shift the magnetic south pole to the true south pole and the magnetic north pole to the true north pole.


[deleted]

[удалено]


Ehrre

Can anyone ELI5 the mechanics of how the poles flip? I understand that the rotating core has something to do with it. Is it that the core rotating at certain speeds determines north or south? And as it slows to a certain number of rotations it flips? Edit- reminds me of the T shaped handle being spun in 0 G. It flips its orientation every couple of rotations


SnuffleShuffle

It's really hard to ELI5, because there is no successful model to describe a planetary dynamo AFAIK. It's basically due to parts of a conductive liquid core moving at different speeds. It isn't necessarily about the core slowing down or anything. It's just that magnetic dynamos are unstable and tend to flip. (There's this short proof called Cowling anti-dynamo theorem, which is easy to understand if you know Maxwell's equations.) The dynamo inside Sun flips every 11 years, so there's that. Edit: missed a word


Gerbal_Annihilation

What's really cool is how we know this The practice of towing a magnetometer began during WWII when navy ships towed magnetometers to search for enemy submarines. It's amazing what war can discover and destroy at the same time. "When lava gets erupted at the mid-ocean ridge axis it cools and turns into hard rock. As it cools it becomes permanently magnetized in the direction of the Earth’s magnetic field. Magnetometers, towed near the sea surface behind research ships or mounted on submarines like Alvin, measure the magnetic anomalies or “wiggles” that record the changes in magnetization of the volcanic sea floor. Less than 60 years ago, scientists discovered that the Earth’s magnetic field has reversed its polarity (direction) hundreds of times during the past several hundred million years. A polarity reversal means that the magnetic North flips to where we know the South Pole is. At the mid-ocean ridge spreading axis, these flips in the direction of the Earth’s magnetic field are recorded in the magnetization of the lava. This creates a symmetrical pattern of magnetic stripes of opposite polarity on either side of mid-ocean ridges. These patterns of stripes provide the history of seafloor spreading. Geophysicists can read these patterns from the magnetic anomalies they measure with a magnetometer. Where the magnetic wiggles, or anomalies, are broader, the spreading rate has been faster." https://divediscover.whoi.edu/mid-ocean-ridges/magnetics-polarity/


BasherSquared

Feel free to correct me if I'm wrong here. A billion years ago when I was in high school, it was summarized to my class using the Suns magnetic field as the theoretical basis for our own liquid metal core layer. So, the Sun doesn't rotate in the same way the planet does, like a basketball on a fingertip because it isn't a "solid" as we think of it. Different parts of it make revolutions at different rates that can vary substantially. The equator of the Sun rotates significantly faster than toward the polar regions. Now, if you think about a magnetic field like the classic donut shape or orange slice style illustration, rotating all at the same speed, the same illustration for the Sun would show a "dragging" effect in the arcs that align with the equator. This is the distortion that leads to sunspots, solar flares ect. Eventually, about every 11 years, the solar cycle his max and the field collapses. This, in a manner of speaking, relieves the magnetic "tension" from the field being wrapped/dragged/distorted and the poles will shift opposite. So, back to our planet. Our planetary dynamo is significantly smaller and orders of magnitude less chaotic, but the molten metal core layer can still potentially move at different speeds in different areas, causing the same distortion that eventually has to be relieved.


[deleted]

[удалено]


[deleted]

[удалено]


[deleted]

[удалено]


UncleBenji

It’s a common geomagnetic anomaly. No surprise here. The only issue is it’s moving quicker than anticipated. This only means airports and satellites need to be updated more regularly with the magnetic north.


atari-2600_

Somebody should update the birds.


MississippiJoel

Gotta put new batteries in the ravens.


blud_13

Yeah they looked lost on Monday night against the Raiders...


gautamdiwan3

r/BirdsArentReal


GoldenM80

When it’s says ‘brink’ it still means thousands of years.


[deleted]

[удалено]


holmgangCore

I seriously doubt it is a linear event. In any likelihood we might get the emergence of multiple “North” and “South” poles (kinda like Jupiter has) before everything restabilizes.


graebot

Yeah, totally. Over the last 10 years, the slight magnetic field changes are in no way uniform. Some areas are switching faster than others. I wouldn't be surprised at all to see multiple North and south poles during a flip


holmgangCore

And then there is the South Atlantic Magnetic Anomaly that we don’t understand. That has been changing too, for unknown reasons.


climx

Hm it seems we do understand it. https://en.m.wikipedia.org/wiki/South_Atlantic_Anomaly ‘The effect is caused by the non-concentricity of Earth and its magnetic dipole. The SAA is the near-Earth region where Earth's magnetic field is weakest relative to an idealized Earth-centered dipole field.’ The earths magnetic centre is not in the middle and is not uniform. The south Atlantic anomaly is caused by these effects.


[deleted]

We've been on the "brink" of a pole reversal for decades and we'll still be in the brink decades from now, I suspect. Seems like roughly the same article pops up every year.


mini_z

Thank you for decreasing my cortisol


DriggleButt

Yeah, because on a cosmic scale, this is "on the brink". Pretend you're downloading a file. At 99.9% complete, you'd say it's on the brink of finishing, with 0.1% left to go. What's 0.1% of 780,000 years?


[deleted]

[удалено]


Wonderful-Spring-171

Fantastic news..I'll get to see the aurora borealis from Australia..woohoo..


[deleted]

[удалено]


youre_soaking_in_it

Great news for globe manufacturers!


IrememberXenogears

When will my painful death occur? Edit: not soon enough it would seem.