Posted on 01/08/2011 6:09:58 AM PST by equaviator
An airport in Tampa, Florida, has had to temporarily close its runways to keep up with Earth's magnetic north pole, which is drifting toward Russia at a rate of 40 miles per year.
Fox News reports that the international airport was forced to adjust the signs on its busiest runway Thursday because pilots depend on the magnetic fields to navigate. The runway will be closed until Jan. 13, and will re-open with new taxiway signs that indicate its new location on aviation charts, the Tampa Bay Tribune reports.
Paul Takemoto, a spokesman for the FAA, says the Earth's magnetic fields are constantly in flux -- but rarely so much so that runway signage needs to be changed. "You want to be absolutely precise in your compass heading," he told Fox. "To make sure the precision is there that we need, you have to make these changes."
"The Earth's poles are changing constantly, and when they change more than three degrees, that can affect runway numbering," FAA spokesperson Kathleen Bergen told Fox News. It's unclear whether any other airports will have to adjust their runways.
Earth's magnetic field, which still flummoxes those who study it, "is thought to be generated deep inside the planet," LiveScience writer Jeanna Bryner explains. "An inner core of solid iron is surrounded by an outer core of molten iron. They rotate at different rates, and the interaction between the regions creates what scientists call a 'hydromagnetic dynamo.' It's something like an electric motor, and it generates a magnetic field akin to a giant bar magnet."
Sometimes, the poles completely flip -- and presumably when that happens, many bigger changes are afoot than modest tweaks to airport signs. The last time the planet experienced a polarity flip was 780,000 years ago.
Of course, this all presupposes that the pole is shifting, rather than the pole staying in place, and the earth shifting. A shift, or tumbling of the earth would explain colder winters and hotter summers, for example.
Have you seen the animations of the field on this site? They are huge files, but interesting:
http://geomag.org/info/declination.html
I blame it on Santa Claus. He has wanderlust.
“...vertical pivots...”
-
Ahhh-yesssss; makes perfect sense, now.
I’ll check them out—thanks!
Sorry, my fault...I should’ve included (/sarcasm) with my comment.
As an ex-Navy controller, I was checked off on that stuff a long time ago. But, thanks for the refresher course...
Yes, the earth does precess about its axis:
http://www-istp.gsfc.nasa.gov/stargaze/Sprecess.htm
And as you can read on that site some see a link between the precession and ice ages. But, the earths north magnetic pole has moved nearly 1,100 km in the last century:
http://www.physorg.com/news8917.html
I am no expert on climate, but I would suspect if the true axis of rotation of the earth had moved that far there would be huge climatic changes.
Are runways labeled by magnetic or true headings?
True headings makes more sense to me, but I don’t know.
In Boy Scouts, we always figured in the local declination to find true.
I would think that airplane navigators would have access to the latest declination and be able to adjust find true headings, then line up with runways (labeled in true headings).
Or in times of stress, you just fly by the compass?
We had better repaint the numbers, or many years in the future, when the aliens come to land on our desolate, empty planet, they will have trouble lining up on the runways.
One of these days, we are all going to wake up with everything upside down living on the wrong side of the Earth.
Don't say you were not warned.
Interesting. Thanks.
I wasn’t sure what the incredibly unhelpful article meant by ‘heading towards Russia’.
I thought they meant it was heading west, not north. If West, then Florida would shift. Since it’s moving north, the declination won’t shift much.
That would explain why it’s only this airport, as they’ve probably not moved it since it was built.
As a former Naval Aviator, thanks for all the times you & your fellow controllers talked us down out of the goo.
I salute you, sir!
By the way, did you hear the story from the Vietnam war about a Continental 707 inbound to DaNang from the north. DaNang had to scramble a flight of Phantoms to the north, so the DaNang controller told the Continental, "Give me a left 360."
The Continental pilot said, "It costs my airline $200 every time I do a 180."
The controller, probably a young NCO, came back quick as a wink, "Well then, give me $400 worth to the left!"
The story talks only about this one, but it's been happening at others, and the trend will accelerate.
bboop: Of all the runways, at all of the airports, all over the world... the magnetic shift has resulted in re-designation of just this one?
See above.
By way of further explanation, the strength of the geomagnetic field is decreasing globally. Geophysicists speculate that we are entering a transition period that will eventually result in another pole reversal. (How soon they expect this, I don't recall.)
During a transition such as the present one, the overall decrease in field strength leads to an exaggeration in regional variations. This also leads to (comparatively) rapid shifts in the position of the poles, and to the acceleration of shifts in the local declinations.
It makes for an increasingly disordered map of said declinations.
Agree tuning to WWV for full report.
In case the sites you posted didn't mention it, it's important to clarify that the true north pole (axis of rotation) isn't what's moving during precession (that is known as true polar wander and is very slight [15 miles over a million years?]), and this topic is totally unrelated to the magnetic-pole wandering. The rotation is still around the same axis--the same north and south points on the globe.
But, as you wrote, the earth is wobbling in space such that the axis was pointing generally toward Vega as the glaciers were receding 12,000 years ago and by ancient Egyptian times, it was pointing toward Thuban. It's near Polaris now, and will be pointing toward Vega again as our north star about 14,000 years in the future. Of course, after that, the circuit will take it back to Thuban. (Contrary to the claims of some misunderstanding New Agers and Catastrophists, scientists aren't claiming it will "jump" or "shift" to these new stars--they are just markers on the circuit it takes in its wobble.)
So the precession of the axis of rotation itself in space is much slower than the movement of the magnetic pole on the earth itself, relative to the axis of rotation. If the axis of rotation had moved 20 degrees down to where the magnetic pole was early last century, we'd have larger problems than a little debate on climate change!
*Note that besides precession, there are other orbital cycles that add to the climate forcings that must be taken into account (eccentricity, obliquity, orbit inclination, elliptical precession, maybe others?). I'm likewise not an orbital mechanics or climatology expert, but in a former life I was doing climatology, so I think I got this mostly right from memory. Still, confirmation is up to the reader, as I'm the very model of a modern Internet commentator--totally lost without web access!
There has to be a way to tax Americans to keep it from being outsourced to Russia.
Before it makes a total move to Antarctica.
YOW - FreeRepublic is agonizingly slow today, but I did get your message. Thanks for the precession description. I am no expert on it, but I agree with you if the axis of rotation were moving along with the magnetic pole it would make for some interesting changes to life on the planet.
I am through for the day on FreeRepublic - can’t take the waiting.
Also keep in mind that Earth’s magnetic field provides our “deflector shield” against solar storms.
A weaker magnetic field means a weaker shield. God alone knows what might happen if the magnetic field drops to near zero during a pole shift (since none of us were around during the last one).
With shields down (”Captain ...!”) could we be cooked off the planet if the Sun decides to throw up? And with the 11-year solar “maximum” due by 2012 or 2013, might that leave us open to extinction?
Stay tuned. It could get interesting!
And, thank you for your service!
I didn't miss the word global, I missed the concept of truthful reporting of facts, not inventing of data to fit a specific agenda.
There is no proof of global warming and man's activities.
The same "scientific methods" that are being used today to further this idea, were used 35 years ago to foist the idea of a new ice age.
I'm not a "scientist, but don't piss down my leg and tell me it's raining, and yeah, I think I can see Russia, you smug "scientist".
Ever see the sun?
The reminder....though unnecessary...is appreciated.
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