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Ship Logs Suggest Upcoming Polar Reversal
Nyerp writes "Researchers are using naval logs dating back as far as 1590 to arrive at better estimates of the decline of Earth's magnetic field. The results suggest that there may be a reversal of earth's magnetic field in about 2000 years." Also worth noting, our ancestors have lived through a number of polar reversals, and we're still here, so no need to fret!
Birds in the southern hemisphere already fly north for the winter.
That should tell you more than anything about birds:
They prefer to be warm and they don't give a damn about the magnetic pole.
(actually, you would probably confuse some birds, but its the warmth they are seeking, not a compass bearing)
liqbase
780 million years ago, there was nothing close to a monkey on earth. There wasn't even any ammonites IIRC. I think you mean 780,000 years ago.
As for your skin cancer concern, I saw a show about the very topic of magnetic field reversal on TV about one year ago. They explained basically what this article explains about the field weakening and all that, and they answered to the question of whether cancers due to the the lack of a magnetic field would wipe all of us out of the surface of us, and the answer was that the number of cancers due to that wouldn't be that significant, however I forgot the estimates.
You just got troll'd!
Components in satellites are rad-hardened because the Earth's magnetic field does not protect them from solar radiation. Broken satellites will not be much of a worry. The increased levels of solar radiation on the ground will be.
The CRT tube is tuned to negate the magnetic influence in the hemisphere its designed for.
If you take a Northern tube and go to Australia with it (or vice versa), the screen may need correction.
See here for more info
liqbase
Not entirely. There will actually be several poles.
The Earth's magnetic field isn't just a dipole (2 pole) field. There are other components of the field, quadurpole (4 pole), octopole (8 pole), etc.. Normally, these components are at least on oder of magnitude weaker than the dipole component. During a magnetic field reversal, the dipole component is so weak that the other components become important. The Earth will then have several sets of weak magnetic poles, at various places around the Earth.
Well, sort of. Satellites at orbits that take them through the South Atlantic Anomaly have to withstand a few minutes unprotected by the magnetic field per orbital cycle. Their lifetimes would definitely decrease if they were exposed to the radiation the entire time, I have no idea by how much. Then again, since the Van Allen belt exists due to the trapping of solar wind by the Earth's magnetic field, the satellites might be fine after all.
Warning: Opinions known to be heavily biased.
As the Earth's magnetic field fluctuates during transition (which we're already seeing), it affects more than the compasses. Our protection from solar radiation substantially decreases as well. Which means that cancers on Earth will go up, but also that satellites will be more likely to fail. So those satellites might just fall out of the sky sooner than you think. Nova had a really good special on the topic a while back, called Magnetic Storm.
As for GPS (the most accurate versions) two appliances at opposite ends of a vessel together with suitable calculations would give you the orientation of the vessel. (I have no idea if this is ever done.)
GPS can, and is, used for attitude determination. You dont need multiple receivers, but rather multiple antennae feeding into a single receiver. The antennae do not have to be spaced far apart, baselines of .5 m have been shown to give good results. The attitude algorithms utilize carrier phase differencing to determine a roll-pitch-yaw measurement down to an accuracy of fractions of a degree.
Maybe something like this occuring leads to accelerated mutations and changes in the human genome (or all animals for that reason).
This is extremely unlikely. We probably get most of our protection from solar and cosmic radiation from the atmosphere, not from the magnetic field. There may be minor ground-level radiation increases during a reveral, but probably nothing signficant. The most significant effect will be spectacular aurorae all the way to the equator!
Significant areas around the poles are not protected by the magnetic field - in fact the field focuses charged particles to there, causing the aurorae. Are there any reports of people and animals in those regions suffering increased mutation rates? I doubt it.
No need for two GPS receivers. If you are moving, the GPS can easily tell which direction you are going, which is more important than the direction you are facing anyway (especially on a boat or plane where they might be different without an easy way to tell).
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}