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Old 12-18-2019, 03:22 AM   #1
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Magnetic North moving

Interesting. I wonder what effect, if any, this will have on basic navigation?

https://www.forbes.com/sites/trevorn.../#866df21201fe
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Old 12-18-2019, 03:34 AM   #2
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Lousy but interesting article. I say lousy because the wriiter mentions the shift will affect navigation but fails to say how or why or what will be the negative effects.
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Interesting. I wonder what effect, if any, this will have on basic navigation?

https://www.forbes.com/sites/trevorn.../#866df21201fe
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Old 12-18-2019, 04:58 AM   #3
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Aware of that 60 years ago after reading navigation charts.
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Old 12-18-2019, 05:08 AM   #4
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Greetings,
It may not affect basic navigation all that much. Electronics shouldn't change as it is satellite based and your old faithful magnetic compass will just have to be "retuned" or swung. https://setcompass.com/MagneticVariationAdjustment.htm


I'm guessing any electronic changes can be achieved by a software patch.
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Old 12-18-2019, 06:21 AM   #5
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Not a very good article for a Senior Science Contributor!
It seems he is alluding to Variation which has been changing for a LONG time and the rate of change is shown on all nav charts.
First he states the rate is increasing but then states it slowed... which is it and how does that compare to what's published.
It doesn't affect nav as long as the navigator uses True N or does the right adjustment to get to Magnetic and the Compass North.
I seriously doubt the military is concerned?
Somewhat fake news in my book... or at least nothing new so not really news without a better explanation IMHO
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Old 12-18-2019, 08:44 AM   #6
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I hope it does not affect Santa's navigation.
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Old 12-18-2019, 09:27 AM   #7
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Mr Claus should be OK if he turns off the MACAS system before flight.
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Old 12-18-2019, 03:03 PM   #8
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"All models are wrong but some are useful."

What has happened is that the magnetic pole has moved faster than the model. The model need to be updated to reflect this change in rate.

GPS and glonass are good for locating position, but can only point in a direction if the receiving device is moving. Remain stationary or obstruct or lose the signal and you may have an incorrect heading reading.

Magnetic compasses are good for defining direction and are used to compliment the accuracy of satellite arrayed location. Although I would guess that ring laser gyroscopes are used more often now.

But you will notice, that magnetic compasses are still required on commercial vessels and airplanes as primary devices.

Why would the military be interested?

Magnetometers are used to detect anomalies in the Earth's field. Like the ones on the rear of a P3 Orion or a Seahawk.

They are also used for guiding and positioning horizontal directional drilling rigs. Like the ones I can literally see out of my window right now.
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Old 12-18-2019, 03:23 PM   #9
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Old 12-21-2019, 12:03 AM   #10
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Quote:
Originally Posted by RT Firefly View Post
Greetings,
It may not affect basic navigation all that much. Electronics shouldn't change as it is satellite based and your old faithful magnetic compass will just have to be "retuned" or swung. https://setcompass.com/MagneticVariationAdjustment.htm


I'm guessing any electronic changes can be achieved by a software patch.
Greetings Mr. RT,

I agree the moving pole will not affect navigation that much. Its moved much more during the years even before GPS. It moved in the years before LORAN and ships still (mostly) got where they were going. Actually for us in North America it is moving in such a way the field lines are hardly changing, so I don't think we will even see much change in declination.

I disagree a compass will have to be swung due to changing of the pole location. The compass should be checked for accuracy when any ferrous metal/electonics/wiring is added/fiddled with/removed in its vicinity; otherwise it will still point to magnetic north without fail, regardless of where the pole is.

What will need updating is declination information on our charts/maps. (Both print while we still have them and digital.) Until and unless the magnetic pole decides to stop at the geo-north pole, we will always have compass error from magnetic north to true north.

The magnetic variation adjustment is the one you do (math in your head, or the computer in your plotter) to convert from magnetic north to true north, based on the published declination shown on the compass rose on NOAA charts and other sources.

ps: Agree poor article, nothing sensational or even newsworthy about here. Interesting to see an update on the pole position though, I don't think I had seen an update on it in 8 or 10 years
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Old 12-21-2019, 12:26 AM   #11
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Greetings,
Mr. f. You are correct, of course. My power squadron courses were some 35+ years ago and the older I get, the more severe and frequent the...


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Old 12-21-2019, 01:35 AM   #12
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I learned a great deal about the changing declination about 11 years ago.

In my younger days (teens/early 20s) I learned a lot about land navigation and underwater navigation, both of which depend on figuring accurate bearings from magnetic to true north and back. I grew up in the PNW and our declination was always 19 degrees. I did it so much that calculation became automatic for me.

Flash forward to NOAA dive school in 2008, and we were doing some underwater navigation work. I flabbergasted to find the declination was now 17 degrees. It took me a while to get the new number in my head, because as far as I knew during my youth it was relatively stable at 19 degrees. Even though a dive compass is not accurate to the nearest degree, the tests had to be!

Now tonight I looked up what it is for my area, and it is 16 degrees (actually a tad less.)

The Admiral looked at me with a critical eye when I told her that "back when we were married the declination was 19 degrees." She said "You remember THAT?"

#thingsouradmiralsshaketheirheadsat

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Old 12-21-2019, 10:01 AM   #13
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So, let me ask...

As it is known that Earth experiences magnetic field reversals [evidentially in from 100K to 50M year intervals]... is there any way to predict [with any sort of accuracy] peturbance experienced/manifested on planet surface and planet core during and soon [in 1 to 100 years] thereafter the reversal?

And, seeing as the article mentions - "... recent weakening of Earthís magnetic north pole on the order of 10 to 15%.": Is that a normally experienced fluctuation?. What is the predicted %age of weakening that may induce Earth's magnetic field reversal?

Quote from article linked on first post:

"In geologic record there is a large range in time between magnetic field reversals from every 100,000 years to every 50 million years. Given that and the difficulty in measuring the activity within Earthís outer core means itís nearly impossible to predict a magnetic field reversal in advance. However, we have seen a recent weakening of Earthís magnetic north pole on the order of 10 to 15%."
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Old 12-21-2019, 11:32 AM   #14
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Quote:
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GPS and glonass are good for locating position, but can only point in a direction if the receiving device is moving.
There are GPS compasses than work perfectly even when stationary. Not part of your typical $10 GPS module, but not that expensive to make either, should the magnetic pole cease.

In the US and most of the world, runways are named marked with the magnetic heading, so a runway with the heading 190 degs M would be called Runway 19. At the airport where I fly most, a couple of years ago they had to rename and remark the runways. Runway 19 went to runway 20.
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Old 12-21-2019, 12:13 PM   #15
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DDW, I noticed several runways near me had changed. 9-27 has been changed to 10-28
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Old 12-21-2019, 01:54 PM   #16
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Quote:
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So, let me ask...

As it is known that Earth experiences magnetic field reversals [evidentially in from 100K to 50M year intervals]... is there any way to predict [with any sort of accuracy] peturbance experienced/manifested on planet surface and planet core during and soon [in 1 to 100 years] thereafter the reversal?

And, seeing as the article mentions - "... recent weakening of Earth’s magnetic north pole on the order of 10 to 15%.": Is that a normally experienced fluctuation?. What is the predicted %age of weakening that may induce Earth's magnetic field reversal?

Quote from article linked on first post:

"In geologic record there is a large range in time between magnetic field reversals from every 100,000 years to every 50 million years. Given that and the difficulty in measuring the activity within Earth’s outer core means it’s nearly impossible to predict a magnetic field reversal in advance. However, we have seen a recent weakening of Earth’s magnetic north pole on the order of 10 to 15%."
In addition to questions I ask in my post #13 quote above...

Does - "... recent weakening of Earth’s magnetic north pole on the order of 10 to 15%." - Mean there has been equivalent recent strengthening on south pole magnetic field? Or, is there potential for Earth's magnetic field[s] in general to loose and/or regain magnetism as millenium go on?
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Old 12-21-2019, 03:35 PM   #17
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DDW, I noticed several runways near me had changed. 9-27 has been changed to 10-28
NOAA does a "magvar" survey of every certificated part 139 airport about every ten years, often leading to such an adjustment. Not unusual to reverse it ten years later, as the magnetic pole moves very erratically, occasionally as much as 80 miles in a day and the isogonic lines even more so.
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Old 12-21-2019, 04:08 PM   #18
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Worth Reading:

World Magnetic Model 2020 Released

https://www.ncei.noaa.gov/news/world...-2020-released

What If Earth's Magnetic Poles Flip?

https://www.livescience.com/18426-ea...oles-flip.html
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Old 12-21-2019, 04:58 PM   #19
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When the poles flip?

Guess we better get used to helming in reverse!
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Old 12-21-2019, 05:51 PM   #20
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Quote:
Originally Posted by Art View Post
So, let me ask...

As it is known that Earth experiences magnetic field reversals [evidentially in from 100K to 50M year intervals]... is there any way to predict [with any sort of accuracy] peturbance experienced/manifested on planet surface and planet core during and soon [in 1 to 100 years] thereafter the reversal?

And, seeing as the article mentions - "... recent weakening of Earthís magnetic north pole on the order of 10 to 15%.": Is that a normally experienced fluctuation?. What is the predicted %age of weakening that may induce Earth's magnetic field reversal?

Quote from article linked on first post:

"In geologic record there is a large range in time between magnetic field reversals from every 100,000 years to every 50 million years. Given that and the difficulty in measuring the activity within Earthís outer core means itís nearly impossible to predict a magnetic field reversal in advance. However, we have seen a recent weakening of Earthís magnetic north pole on the order of 10 to 15%."
Quote:
Originally Posted by Art View Post
In addition to questions I ask in my post #13 quote above...

Does - "... recent weakening of Earthís magnetic north pole on the order of 10 to 15%." - Mean there has been equivalent recent strengthening on south pole magnetic field? Or, is there potential for Earth's magnetic field[s] in general to loose and/or regain magnetism as millenium go on?
The current rate of change of the location of magnetic north has some scientist suggesting we may see north and south poles reverse this century before the poles become more stable. Magnetic poles are less of a concern for me.

The earth wobbles as it rotates. The equator as it is known is migrating already. Lat/Long will change. Climate change? Hell yes because the axis of rotation facing the sun is changing.
Having lived in this house for decades I asked the wife to point to where she remembers the summer sun setting, and then we started to observe it is setting north of the where we had gotten used to it setting.

Changes in the Sun's Position
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