Earth's Magnetic Field Flip Could Happen Sooner Than Expected | Hacker News Reader

Earth's Magnetic Field Flip Could Happen Sooner Than Expected

scientificamerican.com

119 pointssytelus63 comments

One flaw that bugs me in the article: "the dangerous cosmic radiation spewing from the sun in the form of solar winds." From the Wikipedia: "Cosmic rays are immensely high-energy radiation, mainly originating outside the Solar System." It might not be strictly wrong (as language leaves open that some cosmic rays may come from our sun; and the Wikipedia solar wind article has "The solar wind affects the other incoming cosmic rays interacting with the atmosphere of planets."). But cosmic radiation is most famous for being very high energy (cosmic scale) and of exotic origin. A small pedantic point, but lack of distinction makes me think of this http://explosm.net/comics/3557/ .

Edit: I know cosmic rays are not typically em-radiation. The name rays (which usually denotes em-radition) is a historic accident. Hence "cosmic rays" and "cosmic radiation" are fairly close terms. And yes our sun produces tons of rays and radiation- but not typically at the "cosmic" energy scales.

I don't mind getting down-voted for being overly pedantic (and perhaps worse yet trying to be pedantic, while being possibly wrong- this isn't my field). But some of the follow-ups really look like they are missing the same type of distinction in the exact manner I was originally complaining about (which is why there is some small value in trying point this out).

Why is this a flaw? Solar flares are a form of cosmic radiation; they're not the only source for it of course, but, as far as I know, one of the (if not the) strongest ones.

I thought solar flares interacted in ways that suppressed cosmic rays (such as http://science.nasa.gov/science-news/science-at-nasa/2005/07... ), not produced them. But it isn't my field, I could easily be the one who is wrong.

The sun definitely produces radiation.

Like light.

But not typically at the so-called "cosmic" energy scale.

"Cosmic" is not an energy scale — it's a word meaning "from space." It's not like cosmic dust is very energetic dust or, more relevantly, like the cosmic microwave background radiation is hugely energetic.

Sun Burn = Radiation Burn

"Cosmic rays" are not the same as "cosmic radiation". Cosmic rays are charged (massive) particles which are moving at relativistic speeds, and are not electromagnetic radiation. In contrast, cosmic radiation consists of photons.

I see the wikipedia article for cosmic rays [0] does state they are radiation, which is misleading and should probably be changed.

[0] https://en.wikipedia.org/wiki/Cosmic_rays

"Radiation" doesn't necessarily mean electromagnetic radiation. After all, alpha- and beta-rays are also called radiation all the time.

Rays usually means em-radiation. But cosmic rays are misnamed from (as they tend to be radiation, but not rays).

Cosmic rays are particle radiation [0], so its not misleading to state that they are radiation.

[0] http://en.wikipedia.org/wiki/Particle_radiation

It can be correct but still misleading. I think, depending on the reader, there's a good chance it's misleading.

Yes, you're correct. My bad. Though, in my experience, "radiation" without a modifier almost always refers to the electromagnetic variety. But I guess that could vary depending on what circles one hangs out in.

This. In medicine, for instance, "radiation" without a modified almost always refers to "ionizing radiation" --ie with enough energy to induce DNA damage by creating free radicals or inducing covalent linkages.

IME in physics, the term "radiation" usually refers to particles whose total energy is much greater than their rest mass. Not all free electrons constitute beta radiation; only those whose velocity is some considerable fraction of the speed of light. Massless particles such as photons, on the other hand, are always radiation according to that definition.

I'm getting lost in terminology: at least one source uses "cosmic radiation" in the exact opposite sense, as a synonym for cosmic rays:

http://pdg.lbl.gov/2008/reviews/rpp2008-rev-cosmic-rays.pdf

I guess it depends on the field one is in. Confusing, though.

AFAIK the term "cosmic radiation" is not really specific. Cosmic rays are cosmic radiation, but the term does not exclusively refer to them.

Cosmic Rays are often started from one singular particle, but by the time they hit the atmosphere, they cause air showers large and small. This is because there's not a whole lot to interact with in space, but there's tons of matter once you start hitting the atmosphere. At ultra high energies, cosmic rays cause extensive air showers leading to radiation in the form of gamma rays, muons, and electrons/positrons through pair production. The electrons are actually called the "electronic shower" There is a distance where the average energy of the photons in the shower is less than 1MeV, causing pair production to cease. This distance into the atmosphere is called Xmax, but it's dependent upon the amount of mass in the atmosphere, not the magnetic field. For lower energy cosmic rays, Xmax is pretty small. For higher energies, Xmax can easily hit us.

I don't think it's pedantic at all. In fact there's another mistake in that same sentence: the "dangerous" solar protons aren't from the solar wind, but irregular events like CMEs and solar flares. The solar wind protons are too low in energy (1-10 keV) to have any penetrating ability, either in the atmosphere or in crewed spaceships.

https://en.wikipedia.org/wiki/Solar_wind

https://en.wikipedia.org/wiki/Solar_proton_event

Here's a comparison of proton sources in one chart:

http://ocw.mit.edu/courses/nuclear-engineering/22-01-introdu...

(disclaimer: not my field)

Cosmic rays also don't get deflected by the magnetic field (either photons or very high energy particles). The atmosphere's density shields us from radiation much more than the magnetic field. Also a full half of the sky's radiation is shielded by the ground.

This is an interesting result. An old paper [1](1988) was my first exposure to asking the question about whether or not periodic pole reversals were tied to other cyclic phenomena such as volcanism, glacial periods, and mass extinctions.

I observe that the magnetic field has a fairly material impact on the upper atmosphere, so it seems reasonable to include it in the models on climate change.

[1] http://www.jstor.org/discover/10.2307/30064982?uid=2&uid=4&s...

"Still, there is no evidence that a weakened magnetic field would result in a doomsday for Earth."... "Researchers think power grids and communication systems would be most at risk."

Somebody give it to me strait, do I need to build a doomsday bunker ASAP and start stockpiling supplies?

Depends on the article you read :) This one sounds much scarier: http://blogs.discovermagazine.com/d-brief/2014/06/10/earths-...

I wonder how it will affect animals that migrate...

It sounds like a relatively gradual process, animals might be able to adapt quickly, they've done it before.

Gradual how? If there's no overall magnetic moment then surely navigation on magnetic field sensing organs will simply fail, if it switches/moves - even gradually - and stays the same strength then the animal likely ends up in entirely the wrong place with the wrong foodstuffs and climate. Can't see that either of those "gradual processes" is going to work well.

Certainly the magnetic field has flipped before but do we know that animals that use magnetism for migratory guidance were able to "adapt quickly". Can you walk us through the evidence?

You're assuming that this is the only method of navigation they have, instead of it being one tool within their navigation tool belt. Also, I'm sure magnetic sensory organs have some natural error to them that they are constantly re-calibrating for. If the reversal happens within the bounds of natural error and recalibration, then I suspect they would have little trouble adapting.

Correct, animals such as homing pigeons primarily rely on sight and landmarks. There are no known animals that exclusively use magnetic fields to navigate.

The Monarch Butterfly uses it when the sun isn't available: http://en.wikipedia.org/wiki/Monarch_butterfly#Migratory_The...

Apparently it "sees" the magnetic fields, but it also relies on the sun. I don't think it's been studied if it can reorient itself at birth if the poles are switched or if it's "hardcoded".

There are some bacteria

https://en.wikipedia.org/wiki/Magnetotactic_bacteria

This is a good point, although I submit that the magnetic direction is irrelevant for their purpose.

I wonder how they manage when flying at night. Do those birds that are more capable night-flyers have superior magnetic senses?

> do I need to build a doomsday bunker ASAP

No. The cost of building and maintaining a bunker is higher than any chance of ever realizing a benefit. This is true for any doomsday type scenario but if you live in a place with dangerously high winds or tornadoes a cellar might be a good place to weather a storm.

> stockpiling supplies?

Yes, you should always stockpile food and water in case of emergency [1]

[1] http://emergency.cdc.gov/disasters/foodwater/prepare.asp

Do they still have that ridiculous law that makes you a potential terrorist for stockpiling more than 7 day's worth of food?

http://www.activistpost.com/2011/12/10-ridiculous-things-tha...

Apparently something like that just happened last month:

http://www.dcclothesline.com/2014/06/23/fbi-raids-home-dange...

As far as I can tell it's not a law, just something that could make you suspicious. Which is still ridiculous but not a crime.

> Apparently something like that just happened last month.

That guy was making booby traps and telling an undercover FBI agent that he is going to kill federal agents.

http://www.tampabay.com/news/publicsafety/crime/fbi-arrests-...

The informants claims turned out to be completely wrong.

>But the claims and allegations may have been blown way out of proportion. After police obtained a warrant to search Winters’ home based on information obtained from a confidential informant they were probably surprised that not only did Winters have no explosive booby troops set up all over his property as had been claimed, he was also far short of having possession of the fifty high-powered rifles that police said he had been stockpiling.

The police claimed he was crazy and plotting an elaborate confrontation with police, but there was no confrontation and the guy turned himself in peacefully.

They are only charging him with building some unspecified "destructive device" without a permit, which he has plead not guilty.

As I recall the Mormon religion states you should have a years supply of food on hand so it's not that suspicious. Presumably it also has some constitutional protection as it's not inherently dangerious or damaging to society.

Edit: Might be 3months https://www.lds.org/topics/food-storage

There is no such ridiculous law, as the (somewhat unhinged) article itself makes clear.

If you hold your nose and click through to the original source they link to, it's even further from your summary, referring to stockpiles of MREs, on a short list that also includes night vision goggles, rifle tripods, high-capacity magazines, and ammunition pouches.

(The flyer seems pretty clearly geared towards "suspicious" militia types).

Uh, MREs are a pretty normal part of a survival kit. I've owned them before. It is a pretty stupid law, even if it's scope is targeted towards militia types.

What law? There is no such law.

Who doesn't have more than 7 days food at some point in the grocery shopping cycle? When I was single, I could have lived for several weeks without going to the grocery and without going out to eat.

Big boxes of ramen, pasta, frozen pizzas, etc.

It's not like I go to the grocery and buy a couple days' worth of food at a time.

Now, with kids, we tend to shop 2x a week, but even with that, even when we're about to go to the grocery, we could, if pressed, survive 7 days without external food. I'd imagine the same is true of most anyone with a kitchen, a pantry, and who is not in extreme financial distress.

If the Earth's magnetic field wasn't protecting the earth, even for a few minutes, tons of high energy particles from the sun would enter our atmosphere. That could be pretty shitty for life on Earth (even if it doesn't mass-extinct any species).

Experts don't think that will happen:

http://en.wikipedia.org/wiki/Geomagnetic_reversal#Effects_on...

The article said that it was previously expected in ~2000 years, then mentioned that the rate is about 10x faster. Assuming (quite possibly erroneously) that the relationship is linear and both of these factoids are accurate, that puts the change on the order of ~200 years.

So it doesn't seem likely that most of us will live to see it. That said, I understood it to be a gradual process and I thought there was a time of little to no magnetic field while it's shifting, which might be disconcerting.

Hopefully it's just a matter of securing power lines and hardening satellites, but I'm not sure whether anyone has studied this in much depth.

The author didn't cite any sources but I suspect they were alluding to the fact that we know (roughly) when the field reversals happened in the recent past, and we also know when the mass extinctions were, and one can then see that the field reversals don't tend to cause mass extinctions.

I guess the main reason is that the Earth's atmosphere also provides a lot of radiation protection, regardless of what the magnetic field is doing.

The concern is that the Earth's magnetic field (likely) weakens around 10% or so during transitions, which leads to an increase in ionizing radiation reaching the surface. This leads to two different risks:

- Biospheric effects, due to increased rates of DNA damage; and

- Infrastructure effects, due to increased radiation damage to satellites, or damages to power grids due to large induced currents from geomagnetic storms.

Infrastructure effects are well understood: higher risk of power or communications outages. You can mitigate that risk by stockpiling water (which is a good thing to do anyway), buying a diesel generator, etc.

On the other hand, biospheric effects are less well understood. There is some statistical evidence of some species going extinct right around pole reversals, and several plausible mechanisms have been proposed, but the evidence is by no means conclusive, due in part to intrinsic limits in the fossil record.

Note however that absence of evidence is not evidence of absence, so biospheric effects cannot be entirely discarded. But it is also unclear what steps could anyone take to mitigate such uncertain but potentially fat-tailed risks, so it is your call.

We also need to take into account cascading effects on a particular event. Lets say, for example global electricity is reduced to 30% of its current supply by radiation damage. I won't say the entire human species may go extinct, but for sure a lot of people will die. Literally nothing works without electricity today, starting from food production, to distribution, to cooking, to supply of water to literally every aspect of our life.

I bet that number will be really high. Like more than 50% of the humans.

I guess what you see then is struggle for the control of resources. A certain powerful groups will control the supply of resources and hence will dictate how every thing will play out from there on.

That is a possible scenario, but one that is only feasible if it were to suddenly happen; by the looks of it though, these effects will not be sudden, and will not be global; it's likely power outages will be slightly more common, but at the same time people can mitigate the effects by adding redundancy or shielding or however it works.

So while the earth may be more susceptible to solar flares, it won't be as dramatic as your scenario (or that of doomsday preppers) states.

"and will not be global"

No one ever dies from a global disaster, death is always very local, one person at a time.

The city I work in exclusively drinks groundwater, which will be undrinkable after the electrically powered sewer system shuts down and there is no electrically produced chlorine to sanitize the water. So a guaranteed million dead people after a couple days without electricity.

Its comforting to the species that the death of everyone in the city represents only 0.01% of worldwide population. Its not very comforting to me that 0.01% of the population being dead represents a large fraction of my family, everyone I know in day to day living, all my coworkers and local customers. That might be a slightly bigger problem for me, than for mankind as a whole.

Of course we're not the only city on the planet that drinks groundwater and dumps treated sewage into the same groundwater source. Some cities in "hurricane land" are used to this problem and have plans and stockpiles. Not our city, of course.

And where I live (as opposed to work) we have deep well water pumps... 1000 ft down. Works well electrically, but once we run out of diesel, we're stuck with the same contaminated groundwater.

Doomsday looks a lot more like the great depression combined with the 1917 flu epidemic at the same time, than like alas babylon or lucifers hammer.

I thought Mars lost water and have thin atmosphere because of loss of its magnetic field.

Mars owes its dry and dusty appearance to its wispy atmosphere, less than 1 percent of the thickness of the Earth's. But it wasn't always that way: The Red Planet formerly had a much thicker atmosphere that probably allowed for liquid water on the surface, an atmosphere that was depleted when the planet's magnetic field faded away.

We are not losing it, it is changing polarity ("flipping"). It may be reduced for a short time while the flip happens. It has happened many times before.

As a short-term solution, I propose iron credits. I'll launch the yellow revolution, whereupon concerned citizens will send our non-profit organization of care some money. I will use this money to plant fields of corn, which will be used to produce bioplastic, which will in turn replace the use of iron (the ferrous metal that started all of this mayhem in the first place) world-wide.

The long-term solution is to place a tax on iron. This price chart (https://bitly.com/Wa4lD3) illustrates an increase in demand for iron. A simple 41.3% tax on iron and iron-based products and on the income of all global citizens and companies that use at least 1 product that contains iron or is made by a company that used something containing iron to produce it will promote responsible and sustainable manufacturing practices. If we don't act now, it'll be too late. Polarity shift levels have risen over 3 inches in the past year alone, and our independent and intelligent panel of scientists estimates that a shift of more than 6 inches over the next 100 years will set us back to the stone age.

Very minor nitpicky grammar point: "... the Swarm satellites — three separate satellites floating in tandem."

Can three things operate in tandem?

No. Tandem also implies one behind the other which, even in the context of an orbit, doesn't make much sense.

does this mean earth is going to rotate backwards, just like it says in the holy bible?

There is no such thing written anywhere in the Bible.

"Behold, I will bring again the shadow of the degrees, which is gone down in the sun dial of Ahaz, ten degrees backward. So the sun returned ten degrees, by which degrees it was gone down.” (Isaiah 38:8)

I completely forgot about that passage. However it was only God playing astronomy tricks to make a particular point; I don't recall any case where there is written that the Earth is supposed to start rotating backwards in the future (or the Sun going in the other direction, etc.)

Not sure what bible you're reading. The earth has always rotated "forwards". In the bible, the closest thing I can think of is this passage from Joshua 10: "So the sun stood still in the midst of heaven, and hasted not to go down about a whole day."

There's this and the one stephencanon quoted downthread; both of them were described as divine acts serving particular purpose at the moment. I don't recall any similar prophecy for the future. And I used to be quite a Bible nut ;).

The Preppers are going to really flip over this.

https://en.wikipedia.org/wiki/Prepper

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