an ancient tree that contains a record of a reversal of Earth's magnetic field has been discovered

www.newsweek.com...

The tree—an Agathis australis, better known as its Māori name kauri—was found in Ngawha, on New Zealand's North Island

The precious thing is this huge, lonely tree grew for some 1700 years across a remarkable period in our planet's history when the Earth's magnetic field flipped some 42,000 years ago, a period known as the Laschamp Excursion.

It seems the Earth is possibly entering what is known as a Magnetic Excursion. I have seen various times listed for past reversals or excursions this article says every 200,000 to 300,000 years and the last one being 780,000 years ago!
Kind of reminds me of yellowstone numbers.

Three super-eruptions at Yellowstone appear to have occurred on a 600,000-700,000 year cycle starting 2.1 million years ago. The most recent took place 640,000 years ago – suggesting Yellowstone is overdue for an eruption.

So this tree may well give Scientists an idea of how long the reversals take to complete, we know the magnetic field now has began moving at an increased rate.

Scientists recently announced the magnetic north pole had moved unexpectedly. Instead of tracking steadily from the Canadian Arctic towards Siberia, it sped up so much that researchers had to update the World Magnetic Model (WMM)—a representation of Earth's magnetic field that is used by GPS systems worldwide.

It could well be this is the reason for the changing climate.

Amazing find!

I have been keeping up with the speed of the reversal and the studied effects here. The earth catastrophe cycle videos include the reversal information.

Earth Catastrophe Cycle
31 videos Last updated on Jun 11, 2019
www.youtube.com...

We know it’s done this most recently 780,000 years ago, so there are people who say it’s overdue. We know that the core is becoming increasingly volatile. The North magnetic pole is absolutely running through the Northern Hemisphere at 55 kilometers a year to the northwest.

That’s an indicator that something unusual is happening inside the core.

We also know that the dipole is weakening fairly dramatically. If you look at satellite imagery, you can see that part of the magnetic field has already reversed in the Southern Hemisphere. This is something called the South Atlantic Anomaly. We know that that “reversed flux patch,” as scientists call it, is moving to the West and that it’s doubled in size in the last 60 years, so it now covers about 20 percent of the planet’s surface.

news.nationalgeographic.com...

edit on 23-7-2019 by SeaWorthy because: (no reason given)

a reply to: SeaWorthy

Lava flows show the same reversals and are more common then trees

originally posted by: PhilbertDezineck
a reply to: SeaWorthy

Lava flows show the same reversals and are more common then trees

If I understand correctly the lave can show it happen but this tree living through it and growing can show how LONG it took to start and complete. This has been unknown perhaps until now.
From the article

Because the Earth's magnetic field has a major effect on how much radiocarbon carbon is formed in the upper atmosphere, these precious analyses will allow us to investigate the magnitude and rate of change when the magnetic field reversed during the Laschamp; something not possible before and of great interest given recent changes in the Earth's magnetic field," Turney said.

Ok found this, so we will now perhaps have this record from the tree.

How quickly do the poles 'flip'? We have no complete record of the history of any reversal, so any claims we can make are mostly on the basis of mathematical models of the field behaviour and partly on limited evidence from rocks that retain an imprint of the ancient magnetic field present when they were formed.

www.geomag.bgs.ac.uk...

Exactly why the northern magnetic pole is moving at a faster rate is not clear.

Remember the changes they had to make recently to the airport runways?
EARTH'S MAGNETIC POLE IS MOVING 'QUICKLY' TOWARD SIBERIA: 'IT'S CLEAR SOMETHING STRANGE IS HAPPENING'
BY HANNAH OSBORNE ON 2/5/19 AT 10:21 AM EST

Earth's northern magnetic pole is moving at an unexpectedly fast rate toward Siberia. Scientists discovered the pole was not where it should be in September last year, and, as a result, had to update the model that tracks its movements. The World Magnetic Model (WMM) is a representation of Earth's magnetic field. It is used extensively in navigation by the U.S. Department of Defense, the U.K. Ministry of Defense and many civilian systems—so knowing exactly where the northern and southern magnetic poles are is of paramount importance.

Bold mine

Exactly why the northern magnetic pole is moving at a faster rate is not clear.

The NOAA said Earth's magnetic field changes because of "unpredictable flows in Earth's core. The north polar region is experiencing one of these erratic changes."

www.newsweek.com...

a reply to: SeaWorthy

I have seen various times listed for past reversals or excursions this article says every 200,000 to 300,000 years and the last one being 780,000 years ago!

As usual, consumer grade science gets it wrong. While the average period between reversals is on that scale the variation is great. Certainly nothing like "every 200,000 to 300,000 years.


Could we be in the early stages of a reversal? Sure. Why not?

a reply to: SeaWorthy

EARTH'S MAGNETIC POLE IS MOVING 'QUICKLY' TOWARD SIBERIA: 'IT'S CLEAR SOMETHING STRANGE IS HAPPENING'

That's one of them. What's the other one doing?
www.ngdc.noaa.gov...

a reply to: Phage

news.nationalgeographic.com...

We know it’s done this most recently 780,000 years ago, so there are people who say it’s overdue. We know that the core is becoming increasingly volatile. The North magnetic pole is absolutely running through the Northern Hemisphere at 55 kilometers a year to the northwest.
That’s an indicator that something unusual is happening inside the core.

We also know that the dipole is weakening fairly dramatically. If you look at satellite imagery, you can see that part of the magnetic field has already reversed in the Southern Hemisphere. This is something called the South Atlantic Anomaly. We know that that “reversed flux patch,” as scientists call it, is moving to the West and that it’s doubled in size in the last 60 years, so it now covers about 20 percent of the planet’s surface.

a reply to: Phage

The distinction between geomagnetic excursions and reversals

The geomagnetic record shows complete reversals of polarity at a rate of 2–3 per million years, with a long-term trend in the interval thought to be due to changes in the solid mantle (Jacobs 1994).

Intervals of constant polarity are punctuated by polarity excursions, events where the magnetic direction departs greatly from the usual geocentric axial dipole (GAD), sometimes achieving the reverse direction for a short time.

Excursions have been discovered in both volcanic and sedimentary records, but it is exceedingly difficult to correlate events at different sites and thus establish them as global.

academic.oup.com...

a reply to: SeaWorthy

Yeah. The dipole has weakened, but it's still the strongest its been for 50,000 years or so. But again, based on the record, saying we're "overdue" doesn't really hold any water. Like I said, we may be in the early stages of a reversal. Or not.

This new evidence is consistent with the factor-of-2 equator-to-pole paleointensity signature of a geocentric axial dipole field and also indicates that the time-averaged field is considerably weaker than the present-day field. The resulting dipole moment provides a new calibration standard for cosmogenic isotope production rates and suggests that the present decrease in geomagnetic field intensity may simply be a return to a more average magnitude rather than a harbinger of a polarity reversal.

source

a reply to: SeaWorthy

This will come as a surprise to no one.

If the milantrovich cycle coincided with a solar flare, thats a SHTF scenario that could send us back to the dark ages.

a reply to: Thecakeisalie

The Milankovitch cycle? Which part of it?

a reply to: SeaWorthy

So the tree grew 42,000 years ago, and shows it living through the magnetic flip (or whatever), but you're saying the last reversal was 780,000 years ago. There's some incorrect math there...

a reply to: Phage

Some feel it is happening now I see the earth changes and even perhaps relates to our fallen flocks with "blunt force trauma".

Significantly, the Steens Mountain record bears evidence of a complete magnetic reversal that occurred at an extraordinarily rapid pace (between 3 and 8 degrees per day) some15.5 million years ago.

Today, much has been learned about reversals in the Earth’s magnetic field. It is now known, for example, that magnetic reversals happen much more frequently than previously surmised, and that they can often occur at incredibly rapid clips. It is also known that the last complete reversal, which occurred 770,000 years ago, occurred over a span of less than 100 years.

He received his Ph.D. at the University of California, Berkeley, and did postgraduate work in Australia before returning to the States where he joined the UC Santa Cruz faculty in 1968.

He has made significant contributions in a number of areas, including volcanology, geochemistry, and tectonics. In the 1970s, he developed a method of more accurately measuring the intensity of the magnetic field in rocks – a method that bears his name. Perhaps his most significant contribution, however, has been in paleomagnetism, where he has been a pioneer in the study of magnetic field reversals.

news.ucsc.edu...

originally posted by: KansasGirl
a reply to: SeaWorthy

So the tree grew 42,000 years ago, and shows it living through the magnetic flip (or whatever), but you're saying the last reversal was 780,000 years ago. There's some incorrect math there...

Not my numbers...Guess this should be asked of scientists.
There are though excursions and full reversals so the numbers may be related to that.

It is also known that the last complete reversal, which occurred 770,000 years ago, occurred over a span of less than 100 years. Much more, however, is still to be learned. Most importantly, geologists continue to debate the cause of these reversals.

news.ucsc.edu...


They do say

The newly discovered kauri tree's rings contain a complete record of a near-reversal—the first time a tree that lived during the entire event has ever been found.

a reply to: SeaWorthy

Yeah. That one in the Steens is interesting (fantastic hang gliding site but pretty damned isolated).

It is also known that the last complete reversal, which occurred 770,000 years ago, occurred over a span of less than 100 years.

Not so sure about that claim.

a reply to: Phage

Perhaps the point of perigee, when the earth is closest to the Sun, if that would happen then zap! apogee no dice.

originally posted by: Phage
a reply to: SeaWorthy

Yeah. That one in the Steens is interesting (fantastic hang gliding site but pretty damned isolated).

It is also known that the last complete reversal, which occurred 770,000 years ago, occurred over a span of less than 100 years.

Not so sure about that claim.

I will listen to your numbers if your credentials are better than his?

I'm more interested in how it got buried in 26 feet of mud.

originally posted by: SeaWorthy

originally posted by: Phage
a reply to: SeaWorthy

Yeah. That one in the Steens is interesting (fantastic hang gliding site but pretty damned isolated).

It is also known that the last complete reversal, which occurred 770,000 years ago, occurred over a span of less than 100 years.

Not so sure about that claim.

I will listen to your numbers if your credentials are better than his?

The guy who wrote that article? Tom Garlinghouse? Or the guys who made the study? In any case, saying "it's known" may be a bit premature.

The complexity of the magnetization, the reversed zones above the proposed MBB and the normal zones that Sagnotti and colleagues found below it lead to the conclusion that this section does not carry a reliable high-resolution record of the geomagnetic field. Thus, we feel that inferences about the stratigraphic position and duration of the MBB are premature.

www.researchgate.net... ly

But who knows.

originally posted by: Thecakeisalie
a reply to: Phage

Perhaps the point of perigee, when the earth is closest to the Sun, if that would happen then zap! apogee no dice.

That would be perihelion. It happens every winter (in the northern hemisphere.)