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Magnetic Field Reversals Unlikely To Be a Problem For Life, Says Astronomer (arxiv.org)
RockDoctor writes: A common trope in "the world is going to end, maybe tomorrow" alarmism is the prospect of the earth undergoing one of its frequent (but aperiodic) magnetic field reversals. Popular conceptions have migrating birds falling out of the sky, satellites and GPS systems no longer working, and much other such silliness. Of course, geologists point out that it has literally all happened before, that there is no significant association of extinction with reversals, and that what evidence there is points to a reversal taking a number of centuries to millennia to achieve. And then the next story comes out and the same old "sky is falling" garbage comes out again.
Just for a change, an astronomer has thrown in his few cents worth. In a letter to The Astrophysical Journal (Warning: source paywalled; alternative source), Manasvi Lingam of Harvard University looks at the implications of a magnetic reversal, or of the "switching on" of the Earth's "dynamo" on the flux of radiation experienced by an organism living near the surface. Lingam deduces that during a reversal (or before the dynamo started) "neither the biological radiation dose rates [...] would vary by more than a factor of 2." Behind the "..." is a prospect which will appeal to those looking for ways to die, as "the atmospheric escape rate" is also somewhat affected by the strength of the magnetic field. As a theoretical astronomer, Lingam agrees with the geological record (yay!) that field reversals are unlikely to have major effects on life, or on the atmosphere, or really, on anything other than astronomers' and geophysicists' gauges and dials. None of this will even slightly slow down the overblown hysteria that accompanies the next twitch of the magnetic field.
Just for a change, an astronomer has thrown in his few cents worth. In a letter to The Astrophysical Journal (Warning: source paywalled; alternative source), Manasvi Lingam of Harvard University looks at the implications of a magnetic reversal, or of the "switching on" of the Earth's "dynamo" on the flux of radiation experienced by an organism living near the surface. Lingam deduces that during a reversal (or before the dynamo started) "neither the biological radiation dose rates [...] would vary by more than a factor of 2." Behind the "..." is a prospect which will appeal to those looking for ways to die, as "the atmospheric escape rate" is also somewhat affected by the strength of the magnetic field. As a theoretical astronomer, Lingam agrees with the geological record (yay!) that field reversals are unlikely to have major effects on life, or on the atmosphere, or really, on anything other than astronomers' and geophysicists' gauges and dials. None of this will even slightly slow down the overblown hysteria that accompanies the next twitch of the magnetic field.
Raining on a good panic parade with your "facts" and your "science".
Won't anybody think of the poor panickers bereft of a good panic?
Eddy currents in the boundary layer between the liquid core layer and the solid core?
What's the current understanding here?
I was taught by slashdot commenters that scientists always like to create alarm and panic in order to raise taxes. What happened here ?
Yeah, yeah, we get it. The nutjobs are "out there" waiting to get you. Ruining everyhing, outside of your control. You are totally helpless. ... Do you realite that you sound exactly like a conspiracy theorist? Only with a reversed polarity.
And this whole OCD rampage of an article emerged from that.
All that's missing is you bursting a vein while shaking your fist.
Or standing on the street corner, in your briefs, denying the NSA leaks or the holocaust.
... hiker who gets lost and starves to death because of a compass that isn't pointing north any more?
... where will it be pointing? will there be a mass recall of compasses?
All stars end up as iron, as it's the lowest energy state that can neither be fused nor fissioned.
A star usually fuses its elements in a chain, and a fraction always ends up as iron, by the time it explodes.
Our sun is not the first generation.
So the cloud it formed in, also contained some iron.
And from that cloud came our planet.
That alone would not be enough.
The key factor is, that it is liquid. Allowind the poles of the iron atoms (and everything else) to line up, at least regionally.
Add spinning, forces from other large bodies and varying levels of liquidity, and you get quite a bit of sloshing stirring chaos in there.
The pole emerges form most polar material lining up.
But of course it isn't precise, and changes all the time in that big mess of poles and smaller poles and arcs and twisting.
And once in a while, the main pole gets so disturbed, that it splits. Then you have multiple smaller poles, and a useless compass.
It takes some time to align into something we and the birds consider useful again.
FFS, Slashdot "editors".
... is often followed by "Hold my beer."
I personal;y have a very simple risk analysis method. It is 50%. Either is happens, or it doesn't.
Don't fight for your country, if your country does not fight for you.
He's a real dick...
The Great Oz has spoken!
By any chance, do you happen to play the lottery?
After all it is 50%. Either you win, or you don't.
All stars end up as iron
Not true. Only stars above a certain mass (much larger than our Sun) get to the point where they can fuse larger elements up to iron. Iron comes from supernova explosions and small stars never do that.
as it's the lowest energy state that can neither be fused nor fissioned.
Again not true. Iron can be fused but the reaction loses energy in the process causing the temperature of the star to drop. In large stars this thermal pressure is what is keeping the star from collapsing and/or exploding. Stars that get to the point of trying to fuse iron will rapidly end of life, often violently. You can fuse and fission iron but not in a way that is a net energy gain.
A star usually fuses its elements in a chain, and a fraction always ends up as iron, by the time it explodes.
Stars have to be much larger than our sun to explode via the chain you describe. You have the basics process more or less right but it doesn't apply to all stars. Small stars have much different end of life processes.
And we want to assure you that is is unlikely it will blow up when you leave the car lot.
Billions of compasses have to be thrown in to the ocean, so i'd say it's a big problem.
"None of this will even slightly slow down the overblown hysteria that accompanies the next twitch of the magnetic field."
"And then the next story comes out and the same old "sky is falling" garbage comes out again."
When every scientific effort documented in TFS is punctuated by this bullshit, it really makes me wonder why scientists even expended the effort to do a study in the first place.
In the face of mass ignorance and stupidity, trying to educate people seems so damn futile.
Panic here:
https://phys.org/news/2018-12-earth-magnetic-poles-flip.html
And EU funded agency to study the "problem":
https://cordis.europa.eu/project/rcn/213916/factsheet/en
There is always money to be made by scaring the public with stuff they don't understand.
Back to the original question, is the earths inner core turning at the same rate as the outer core? Or is it the eddy currents... the explanation seems to vary.
This is the pop science version:
https://www.nationalgeographic.org/encyclopedia/core/
Why the core is iron?
"The iron catastrophe allowed greater, more rapid movement of Earth’s molten, rocky material. Relatively buoyant material, such as silicates, water, and even air, stayed close to the planet’s exterior. These materials became the early mantle and crust. Droplets of iron, nickel, and other heavy metals gravitated to the center of Earth, becoming the early core. This important process is called planetary differentiation."
Why the outer core is liquid?
"The outer core, about 2,200 kilometers (1,367 miles) thick, is mostly composed of liquid iron and nickel. The NiFe alloy of the outer core is very hot, between 4,500 and 5,500 Celsius (8,132 and 9,932 Fahrenheit). The liquid metal of the outer core has very low viscosity, meaning it is easily deformed and malleable. It is the site of violent convection. The churning metal of the outer core creates and sustains Earth’s magnetic field."
Why the inner core is solid?
"The inner core is a hot, dense ball of (mostly) iron. It has a radius of about 1,220 kilometers (758 miles). Temperature in the inner core is about 5,200 Celsius (9,392 Fahrenheit). The pressure is nearly 3.6 million atmosphere (atm). The temperature of the inner core is far above the melting point of iron. .... Geoscientists think that the iron crystals in the inner core are arranged in an “hcp” (hexagonal close-packed) pattern. The crystals align north-south, along with Earth’s axis of rotation and magnetic field."
And the Magnetic field?
"Dynamo Theory ...
Some geoscientists describe the outer core as Earth’s “geodynamo.” For a planet to have a geodynamo, it must rotate, it must have a fluid medium in its interior, the fluid must be able to conduct electricity, and it must have an internal energy supply that drives convection in the liquid.
Earth is the “Goldilocks” geodynamo. It rotates steadily, at a brisk 1,675 kilometers per hour (1,040 miles per hour) at the Equator. Coriolis forces, an artifact of Earth’s rotation, cause convection currents to be spiral. The liquid iron in the outer core is an excellent electrical conductor, and creates the electrical currents that drive the magnetic field."
OK, but on the one hand the orientation of the field is from the inner core's alignment of crystals, on the other its the orientation of Coriolis effects in the liquid layer... a bit of clarity please from an expert? When the field flips, what do you expect to change in the cores?
Is it the solid core that spins differently to the earth, or is it the liquid layer only sloshing around?
A 20 second search on Wikipedia would answer your question...
Wikipedia goes with the sloshing model....
"The Earth's magnetic field is believed to be generated by electric currents in the conductive iron alloys of its core, created by convection currents due to heat escaping from the core. However the process is complex, and computer models that reproduce some of its features have only been developed in the last few decades. ...The motion of the liquid in the outer core is driven by heat flow from the inner core....The mechanism by which the Earth generates a magnetic field is known as a dynamo.[47] The magnetic field is generated by a feedback loop: current loops generate magnetic fields (Ampère's circuital law); a changing magnetic field generates an electric field (Faraday's law); and the electric and magnetic fields exert a force on the charges that are flowing in currents (the Lorentz force)....
Right, you're a Coriolis in the outer core man, fine, so next question, what changes when the core flips south-north?
I'm reminded of similar statements by scientists that an EMP or another Carrington event will have minimal effects on humans or animal life. In both cases (and in this), the problem isn't the direct effects, it's the secondary ones. An EMP will mostly pass through biological tissue just fine, and might not even permanently disable some older cars -- but if the US is out of power for 14 months because no one can get the transformers rebuilt, that particular aspect doesn't really matter, now does it?
For a pole flip, I'm not really concerned about the biosphere (except maybe birds), for precisely the reasons indicated. Rather, how does a magnetic flip affect GPS? Compasses? Does it induce current in the process of the flip? That sort of thing.
Hire a Linux system administrator, systems engineer,
Says tech billionaire
Big problem!
"By the way if anyone here is in advertising or marketing... kill yourself." -- Bill Hicks
I said there is a chain of fusion. From hydrogen, over helium ... all the way to iron.
That fusion chain does not have to happen in a single star.
The first star will explode, long before most of its mass can even think about becoming iron.
A second star just keeps fusing the remains.
But in the end, even a dwarf star will end up wirh iron. In fact there will be a time, when everything will have become iron, and stay that way for a long time.
Of course, geologists point out that it has literally all happened before, that there is no significant association of extinction with reversals, and that what evidence there is points to a reversal taking a number of centuries to millennia to achieve.
There also was no significant damage from the solar storm of 1859, but I thought it was well accepted that if such an event were to happen today, it would be disastrous.
I'm not saying we should fear a magnetic field reversal, only that "it happened before and nothing bad happened" is not an argument that we shouldn't fear it.
satellites and GPS systems no longer working, and much other such silliness. Of course, geologists point out that it has literally all happened before,
We all know that GPS was not affected last time.
Isn't the biggest problem with a magnetic field reversal with all of our technology? My impression is that a big solar even will be something like an EMP, without the Earth's magnetic field. Stuff can be hardened against this, notably satellites and military gear. But with ordinary consumer-grade stuff they generally don't bother, because of cost.
The roads are not going to twist just because the poles flip.
You just need to learn to read a map or the land.
If you are in Colorado you can pretty much tell where you are by what side of the Mountain you are and which one.
Manasvi means intelligent
Lingam means d*ck
So this article was done by "Clever D*ck"
Just saying...
.melborp a eb dluoc sdleif citengam gnisrever woh ees t'nod I
"that field reversals are unlikely to have major effects on life, or on the atmosphere, or really, on anything other than astronomers' and geophysicists' gauges and dials"
Considering that solar wind has been correlated with so many aspects of life and health and that our magnetic shield (which has lost 15% in last century or so and is accellerating) is what protects us from these I find this hard to believe.
Cosmic rays also affect cloud formation so there is a potential environmental impact.
Supporting links:
https://www.ncbi.nlm.nih.gov/pubmed/25295148
https://www.omicsonline.org/open-access/sunspot-activity-influenza-and-ebola-outbreak-connection-2332-2519-1000154.php?aid=78784
https://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays#Human_health_effects
https://physicsworld.com/a/physicists-claim-further-evidence-of-link-between-cosmic-rays-and-cloud-formation/
I said there is a chain of fusion. From hydrogen, over helium ... all the way to iron.
You said "A star usually fuses its elements in a chain, and a fraction always ends up as iron, by the time it explodes." This only a true statement for a fraction of stars of sufficient size. Smaller stars like our Sun do not do this to any meaningful degree.
But in the end, even a dwarf star will end up wirh iron. In fact there will be a time, when everything will have become iron, and stay that way for a long time.
This is simply not true. You need to study the physics involved a bit further. You've got some of it right but your conflating some of the details.
Repainting all the runway numbers over and over.
https://youtu.be/tu-sLX0FbF0 Maybe some there are partial truths hidden among the fearful fantasy. Maybe still something to consider. Like the possibility of a slight temporary weakening of the fields and how they may impact our systems.
When they tell you not to panic, that's when you panic !!!
"Magnetic Field Reversals Unlikely To Be a Problem For Life ..."
Key word there is "life", other than messing with any species that uses the magnetic field to guild its migration path for the most part a collapse and flip of the Earth's magnetic field will have little or no long term impact on "life"
But Technology on the other hand is going to be mostly screwed over by a flip. Something most people don't get is a pole flip won't be a clean instant flip where suddenly your compass is 180 degrees off from where it pointed to before lunch. The poles will move around, the "North" pole could end up on the Equator while the "South" pole has become multiple "poles" scattered around the other side of the planet for awhile. This unstable period could last for years if not decades. But that won't be what fucks over technology..
When the Earths magnetic field starts going wonky the Van Allen Belts, the shield that protects the Earth and, most important to Humans, all the communication/GPS/monitoring satellites in orbit will mostly cease to exist. Many of those satellites are not made to withstand direct exposure to the Sun's radiation for very long. So most of the electronics in orbit will be fried. Also affected will be the Earth's Ionosphere, when it gets hit by strong solar radiation, like during a solar flare or direct exposure to the solar wind the layer becomes opaque to radio, no more GPS or reliable communications via satellite will be able to reach the ground, which will mess with shipping, aircraft, commerce (lots of systems use GPS for their time reference) and even local cell phone connections. And all the copper wire strung all over the planet we rely on for power distribution and communications will be similarly hosed. Read up on the Carrington Event" of 1859 to learn what happens when the Earth gets hit by a LOT of solar wind.
All that said I'm not going to lose sleep over the possibility of a flip in my lifetime. Like the Astronomer said, it won't be a problem for Life because it will adapt to the changes and continue on. And as much as I would dislike it not being able to get GPS driving directions to my hotel or surf the Internet won't kill me.
what evidence there is points to a reversal taking a number of centuries to millennia to achieve.
If you had ever looked at a magnetic field strength estimate taken from a sediment (or igneous) pile of rock, you'd know that fields are constantly changing by large factors. Indeed, anyone who has even the slightest knowledge of geomagnetics knows that during the period of instrumental measurement (~2 centuries) there has been a factor-of-2 decrease in general field strength, and more in some areas. So, anyone designing a system that uses geomagnetics is going to incorporate that possibility in their design. Anyone not doing that is flat-out ignorant, incompetent, or both.
"Equipment designed by ignorant/ incompetent people breaks" - even Slashdot would probably reject that story!
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
The author has released a revision of the paper at the same location as described above. The original version is now here. There are no major changes to the conclusions.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"