Magnetic change?
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The article in the original post implies that they are able to accurately model the expected changes for the next 5 years. The rate of change is increasing, but it is still relatively predictable. To paraphrase Mark Twain, reports of the demise of the earth's magnetic field are greatly exaggerated.
The biggest issue during pole reversal will be increased exposure to solar radiation. With the magnetic poles currently near the North / South geographic poles, the magnetic field directs solar radiation towards N/S geographic poles. This is what 'feeds' the Aurora's. This is also what protects our equatorial and mid-latitudes from solar radiation. During a reversal the magnetic field strength will weaken and the direction will become variable (hence the increasing fluctuation of magnetic variation). This means that our equatorial and mid-latitude regions (where most of us live) will be more exposed to solar radiation. The significance of this is unknown and subject to debate.
many many times. Easy proven where there is continental sea floor spreading in a volcanic place like Iceland. When the lava cools it aligns with the earth’s polarity. Then that lava slowly moves away from the rift and new cooling lava takes its place. You get a neat timeline of flip flops. Older stuff requires more complex dating.
Maybe birds got confused?
Most recently, about 780,000 years ago.
I don't think that one caused any problem for pilots.
Brunhes–Matuyama reversal
I don't think that one caused any problem for pilots.
Brunhes–Matuyama reversal
Shouldn't affect GPS/IRU navigation, except for updating databases to "conform" to magnetic navigation where needed. Shouldn't affect GPS satellite orbits - those are based on gravity (and maybe solar wind), not magnetism.
The magnetic poles and declination lines are always squirming around - in this case just faster than predicted: https://en.wikipedia.org/wiki/Magnet...90_to_1990.gif
And - yes - VORs can be, and are, updated as needed.
The magnetic poles and declination lines are always squirming around - in this case just faster than predicted: https://en.wikipedia.org/wiki/Magnet...90_to_1990.gif
And - yes - VORs can be, and are, updated as needed.
From Wikipedia:
"A brief complete reversal, known as the Laschamp event, occurred only 41,000 years ago during the last glacial period. That reversal lasted only about 440 years with the actual change of polarity lasting around 250 years. During this change the strength of the magnetic field weakened to 5% of its present strength."
Does any electrical equipment depend on the Earth's field at startup?
"A brief complete reversal, known as the Laschamp event, occurred only 41,000 years ago during the last glacial period. That reversal lasted only about 440 years with the actual change of polarity lasting around 250 years. During this change the strength of the magnetic field weakened to 5% of its present strength."
Does any electrical equipment depend on the Earth's field at startup?
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Nothing that I can think of. But with the field down to 5%, low Earth Orbit would be much less habitable than it is now. As long as we can survive radiation on the ground, we should be fine. If the Van Allen belts collapse (partly or fully) higher orbits might actually become safer to use.
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and require the device to be 'waved' in a figure-of-eight motion a few times to properly orientate. Some Drones too (arguably a good thing), need turning by hand in three axis's to align the field.
More importantly, a reduced magnetic field will eliminate the protection from cosmic rays and other space radiation, potentially killing any or everything from power grids to frying sensitive micro-electronics & radio transmission interference. And heavens knows what to biological systems.
Overall, a reversal - more accurately, the period of reversal change - is definitely not a good thing.
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Yes, no worries, except civilisation as we know it will disappear.
One thing no-one is certain about and that's the effect of a low magnetic field during the process of the flip on the ionosphere - it might lead to more (or less) aurora, solar rays reaching sea level, magnetic storms, a significant effect on long range radio transmission etc etc
I guess if it doesn't affect the GPS Satellites etc we can get through
I guess if it doesn't affect the GPS Satellites etc we can get through
The movement of the North Magnetic Pole is dealt with by applying a correction, Magnetic Variation to the magnetic compass. We have been doing this, successfully, from the early days of air navigation and nothing has changed except the rate of change. Published values of Variation over the earth's surface will have to be updated more often, this includes VOR radials.
Incorrect. These gadgets rely on a GPS satelite signal (which may get blocked inside a car / building) and have nothing to to with Earth's magnetic field. Other than magnetic compasses (and systems that rely on a derived magnetic compass signal, but these are all adjustable to allow for a changing deviation), there is nothing we use today that is affected.
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