Magnetic north point moving fast

Cluemeister

Cluemeister

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Cluemeister
Buncha jokesters here, but this is potentially pretty serious for pilots.

On January 30 (delayed due to the US Government shutdown), the World Magnetic Model — which governs modern navigation systems — is due to undergo an urgent update.

This model is a vital component of systems ranging from geopositioning systems used to navigate ships through to smartphone trackers and maps.

The current model was expected to be valid until 2020. But the magnetic pole began to shift so quickly, it was realised in 2018 that the model had to be fixed — now.

“They realised that it was so inaccurate that it was about to exceed the acceptable (safe) limit for navigational errors,” Nature reports.
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So, expect your glass panels to need an update... And if you live near the extremes of the G1000's operational area, better cross your fingers. And toes.
 
Half Fast said:
Any of you bidding for a contract to repaint all the US runway numbers yet?
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That actually makes an interesting point. I have noticed in my recent flights over the past 6 months that a LOT of runways have changed numbers.
 
They're worried about ship navigation in the far north, thinking that the moving magnetic field makes it difficult. But the compass has never been any good up there anyway; the lines of flux dive almost vertically into the planet and make readings unreliable. Until GPS, the sun was used for direction. In some areas it still is.
http://www.nauticapedia.ca/Articles/Compasses_North.php
 
GRG55 said:
That magnetic pole and compass thing is the stuff of 18th century wooden ships.
Bloody good thing we invented the magenta line...
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Because nothing bad ever happens while mindlessly following the magenta line.
 
flyer770 said:
Because nothing bad ever happens while mindlessly following the magenta line.
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It doesn't pay to think too much.
I read that in a Garmin manual. ;)
 
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Ted DuPuis said:
That actually makes an interesting point. I have noticed in my recent flights over the past 6 months that a LOT of runways have changed numbers.
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Trying to remember, what’s the update schedule? Foggy memory but I thought there was a prescribed rw number update schedule. 5 or 10 years?
 
I looked at the chart at the beginning of that article and it appeared to show the opposite of the fear mongering headline. Since 2010 it’s slowed a bit.
 
Salty said:
I looked at the chart at the beginning of that article and it appeared to show the opposite of the fear mongering headline. Since 2010 it’s slowed a bit.
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I thought that too, until I took another sip of coffee. The chart shows increments of 20 years up till 2000. Then a 10 year gap, then a 5 year gap. Changing the gap distorts the perception.
 
woodchucker said:
Trying to remember, what’s the update schedule? Foggy memory but I thought there was a prescribed rw number update schedule. 5 or 10 years?
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Not really a schedule of anytype. The magnetic heading of the runway is usually reviewed if the pavement is rehabed or reconstructed and the markings have to be repainted anyway. Just a convenient time to do it.
 
JOhnH said:
I thought that too, until I took another sip of coffee. The chart shows increments of 20 years up till 2000. Then a 10 year gap, then a 5 year gap. Changing the gap distorts the perception.
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Look again. It’s still slowing.
 
Salty said:
Look again. It’s still slowing.
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After a little more coffee, I think I see what you are looking at. The gap between 2015 and 2020 is smaller than the gap between 2010 and 2015. But 2020 is just an estimate that was probably made a few years ago.
 
It appears the magnetic north is migrating towards the north pole. That would make things simpler.
 
JOhnH said:
After a little more coffee, I think I see what you are looking at. The gap between 2015 and 2020 is smaller than the gap between 2010 and 2015. But 2020 is just an estimate that was probably made a few years ago.
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But is that just an effect of flattening a sphere into a flat map?

But look on the bright side, it looks like it’s getting closer to true north.

:rolleyes:
 
cgrab said:
It appears the magnetic north is migrating towards the north pole. That would make things simpler.
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Looks to me like its about to pass the north pole and currently is at its closest point...which means right now is as simple as it gets!
 
Does this mean that Santa is moving???
 
GRG55 said:
That magnetic pole and compass thing is the stuff of 18th century wooden ships.
Bloody good thing we invented the magenta line...
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Nope. GPS coverage is not completely global. The various maps I find differ a bit, but the coverages look similar to this:

7816824-12121968.jpg


Some of the mid-latitude ocean should be OK but WAAS would be inop. It's the poles that don't appear to be covered well.
 
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SkyDog58 said:
Probably one reason why runways are numbered to the nearest 10 degrees rather than the nearest degree.
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And that is a convienence and somewhat arbitrary. KMCO has four parallel runways (all oriented north south). They are truly parallel. The western 2 are 18-36 L&R and the eastern 2 are 17-35 L&R
 
Coming ice age. Apparently the poles have flipped several times.
 
yetti said:
Apparently the poles have flipped several times.
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The poles flip about every million years, if I recall my university geology correctly. We are overdue for a change. There are concerns that the magnetic field may collapse for a while during the transition exposing us to hazardous 'cosmic rays'.

As I understand it no one really knows how the field arises or what causes the flips.

Pole reversal is the "conclusive" evidence for seafloor spreading which is a key mechanism in the movement of the continental plates. I can roughly recall the Atlantic case.

The US and Europe are slowly getting further apart. There is a volcanic ridge runs down the middle of the Atlantic. As continents move apart the molten rock comes out the slot and solidifies filling the gap. It takes on the local magnetic field as it does so.

midridge.gif


There are consequent bands of opposing polarity baked into the rocks across the Atlantic ocean. This was found round about the '60s when Magnetic Anomaly Detectors became available. The MADs may have been developed for detecting submerged submarines and/or for oil exploration.

seaflor2.gif


Lockheed Orion with MAD boom.

P-3_prototype_NAN1-59.jpg


Theory of Plate Tectonics.
Continental Drift.
Gondwanaland.


Most of the above is likely mostly OK. :)

There is no connection to the accumulation of the greenhouse gas CO2 in the atmosphere.

http://www.phy6.org/earthmag/reversal.htm
 
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Dan Thomas said:
Nope. GPS coverage is not completely global. The various maps I find differ a bit, but the coverages look similar to this:

7816824-12121968.jpg


Some of the mid-latitude ocean should be OK but WAAS would be inop. It's the poles that don't appear to be covered well.
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Pretty sure GPS covers the entirety of the planet’s surface.
 
Dan Thomas said:
GPS coverage is not completely global
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Interesting, I always thought it was global, hence the name. But I'm also not surprised that coverage may lack or be non existent in wide open parts of the south pacific ocean. Is this that map accurate for all GPS? On the Volvo Ocean Races I was pretty the teams had GPS coverage even in those dark areas.. but maybe not?

dans2992 said:
Pretty sure GPS covers the entirety of the planet’s surface
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That's what I thought.. but given that it is generated by geosynchronous satellites I wouldn't be surprised if it is not in all areas available.. does it make sense to operate and maintain a satellite that you don't really need?
 
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