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Dispelling Myths About Geomagnetic Reversal
UniverseToday has an interesting look at geomagnetic reversal, the process in which the Earth's magnetic poles trade places. The article cites known trends and recent studies to debunk doomsday myths and unsubstantiated claims about the process. One such study is attempting to model the earth's core with a 26-ton ball of molten metal. Another recently found evidence that the Earth has a second, weaker magnetic field. "We do know that this magnetic pole flip-flop has occurred many times in the last few million years; the last occurred 780,000 years ago according to ferromagnetic sediment. A few scaremongering articles have said geomagnetic reversal occurs with 'clockwork regularity' — this is simply not true."
Right, such changes in the magnetic field might happen "quickly" on geologic timescales, but would be very slow on human timescales. Such a flip won't be like an EMP going off.
AFAIK the process takes a very long time and would be very gradual and although it may begin soon it would take a long time and allow for everything to adjust, if required.
However, one can never be really sure... any data on effects of previous switches?
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If we tried to live as hunter-gatherers, we'd need to kill off a whole lot more than half of us. World population is now something like 6.6 billion. We didn't reach 3 billion until 1961. In 4000 BC, about the time civilisation was really getting going in Egypt and Mesopotamia, the population of the world was more like 20 million. That's the kind of figure you're looking at for a world of hunter-gatherers. About the same as the population of New York city.
Real Daleks don't climb stairs - they level the building.
The earth's magnetic field is about half a gauss at the surface. It's weaker than the field generated by a refrigerator magnet. I think it's safe to say that the flip is not gonna destroy your electronics.
A more comprehensive chart at a variety of scales (zoomed in on the last ~1Ma (million years) the last 5Ma and over the last 160Ma is available on the relevant wikipedia page about geomagnetic reversals. The fluctuations are anything but "regular". Anyone who describes them that way doesn't know what they are talking about. Sure, like anything, you can calculate a mean duration, but the variance is very high, with durations from 10s of millions of years to 50000 years. "Clocklike regularity"? Sure, if your clock ticks 1 second one time, and 5 minutes the next.
If these were bad events, there would be obvious correlation to major extinction events. There simply isn't, and people have looked really hard (because it would be interesting if there was).
That's utter nonsense. The magnetic field is continuously monitored from orbit by all sorts of satellites. One of many such satellites is Ørsted. There are papers all through the 1990s and 2000s that analyze the data from this and the others. People don't fund surface expeditions to study large-scale magnetic field variations because they've been largely superceded by satellite measurements. The only people interested in surface measurements are usually exploration geologists (e.g., looking for signs of sub-surface mineral deposits).
If you've ever seen a small chunk of pure sodium tossed into a sink full of water in a high school chemistry class ... and then think how much this guy has ...
Here's a blog post with a couple of vids of sodium water reactions. The US military's post WWII disposal of sodium in a lake is particularly impressive.
Loose lips lose spit.
It really isn't. The problem itself is not the reversal itself, but the period inbetween, when the magnetic field will be very small or inexistent. The earth's magnetic field has the effect of diverting charged energetic particles emitted by the sun towards the poles. It's those particles entering the atmosphere that cause the northern lights. Without a magnetic field, they would penetrate more into the atmosphere, possibly causing harm to living beings.
However, this reversal will happen several hundred years from now. By that time, I'm sure that, if I'm alive, it will be because we will have some pretty advanced medicine, capable of handling the increased radiation effects.
I build the navigation systems used in many commercial aircraft. Primary system is inertial, not GPS; input from multiple accelerometers is integrated to determine velocity and position.
I don't think a field change at .0000000000004 Hz is going to induce much current anywhere.
.03% of the world population. Just a doubling of the current rate of death due to cancer would kill 7.9 million people - almost four times that of AIDS. And with sufficient radiation exposure, the cancer rate could well escalate way beyond 2X.
TFA does little to debunk what may be the biggest danger, and that is the disruption of the Van Allen radiation belt, and the protection that it provides to the Earth from cosmic rays. While I'm sure that the radiation belt would re-establish itself to match the "flipped" magnetic poles, it may not do so during the transition period. And this pole flipping may be quick in geological terms, but it may take a number of years, and during that time, part or all of the Earth may be bombarded with cosmic rays. Or, the distorted field may actually concentrate cosmic rays upon parts of the Earth many times what you'd find in space outside the belt. These cosmic rays would cause massive increases in cancer and genetic mutations in all species of plants and animals, and even a stack of tinfoil hats won't help. Much.
Increases in cancers would not be detected in the geological records, and periods of high radiation may explain things like the Cambrian Explosion, where many new species spontaneously appeared. If the field swaps by rotating from pole to pole, the radiation belt will probably just follow along, but if the poles swap by diminishing to zero and then building at the opposite pole, there will be a very dramatic change (and possible collapse) of the radiation belt that could very well affect life on the planet very dramatically (from our perspective). The scourge of AIDS killed 2.1 million people in 2007. That's
Of course, ancient calendars not withstanding, there's no reason to believe any of this is likely to happen during our lifetimes.
I'm a software developer and I once picked up a few college textbooks on aerospace navigation, specifically ones related to control system design (state methods, optimal filtering/control, etc). and I have to say one thing - you sir are a God amongst mere mortals. To say it's tough is an understatement.