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Swarm Data: Earth's Magnetic Field is Weakening 10 times Faster

by betzalel
Tags: data, earth, field, magnetic, swarm
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Jul10-14, 10:39 AM
P: 40
Swarm Data: Earth's Magnetic Field is Weakening 10 times Faster than Recent Past. Why?
Earth's Magnetic Field Is Weakening 10 Times Faster Now
...Previously, researchers estimated the field was weakening about 5 percent per century, but the new data revealed the field is actually weakening at 5 percent per decade, or 10 times faster than thought. (WIlliam: 10 times faster than physically possible if the cause of the geomagnetic field changes is changes at the liquid core/solid core boundary) As such, rather than the full flip occurring in about 2,000 years, as was predicted, the new data suggest it could happen sooner.
Floberghagen hopes that more data from Swarm will shed light on why the field is weakening faster now.
Swarm is the name of three specialized satellites that were launched by the European space agency in November of 2013. The Swarm satellites are capable of measuring the entire geomagnetic field with laboratory accuracy.

What the first release of the Swarm data has confirmed is an astonishing, unexplained, changed to the geomagnetic field.

The geomagnetic field intensity which had been dropping at 5% per century, is now for unexplained reasons dropping at 5% per decade, ten times faster . now...."

This is astonishing - a paradox - due to the counter emf principal and the physics of the deep earth. By Maxwell's equations applied to a conductive liquid, a counter emf and a counter electric current is generated if there is a change at the liquid core/solid core boundary to resist any field changes. Due to the counter emf principal deep core initiated changes to the geomagnetic field take thousands of years to make large changes to the geomagnetic field intensity and significant changes to the geomagnetic field configuration.

In the last decade the geomagnetic specialists have found unequivocal proxy evidence of significant geomagnetic field changes that are ball park 10,000 times too fast and 100,000 times to large in magnitude to be caused by a core based mechanism. These abrupt significant changes to the geomagnetic field are called archaeomagnetic jerks (this is confusing terminology as an archaemagnetic 'jerk' geomagnetic field change is orders of magnitude too large and too fast to be caused by changes at the liquid core/solid core boundary which is the assumed cause of geomagnetic jerks. i.e. geomagnetic jerk and archaeomagnetic jerk must therefore have completely different causes.)

The hypothesis to explain paleo geomagnetic field record changes that are called archaeomagnetic jerks (the suffix archaeo is used as the phenomena was found by studying field changes recorded in fired tiles that were laid in chalets and palaces.) that are ball park 10,000 times too fast to be caused by a core based mechanism is that there is suddenly a plume of liquid from the core moving into the mantel.

The problem with the plume hypothesis is there is no mechanism to suddenly cause liquid core plumes moving into the mantel to explain the observed sudden changes to the geomagnetic field intensity and configuration in the last 10 years, using the plume hypothesis. The sudden observed change of the northern magnetic drift velocity and the American continents magnetic field intensity drop would require there to be liquid core plumes moving into the mantel in Greenland and throughout the North and South American continents, starting roughly 10 years ago.

The plume hypothesis to explain the sudden unequivocal changes (these changes have been known to be occurring for at least 10 years from other measurements, which was the reason why the half billion dollar Swarm program got funding.) to the geomagnetic field is ridiculous, absurd, not physically possible. There is nothing that could suddenly change deep within the earth to suddenly cause worldwide plumes of liquid core material, from physically far removed regions of the earth, to simultaneously start flowing into the mantel.

1. The Greenland plume is required to explain the fact that the northern magnetic pole drift velocity suddenly increased by a factor of 10 starting sometime in the mid 1990s. The plumes over the two American continents is required to explain the massive region of magnetic field intensity drop that the Swarm satellite data found.
2. It should be noted that the geomagnetic field intensity has dropped by 60% over a large region in the Southern Atlantic.
3. Observation 1 and 2 are consistent with the assertion that a geomagnetic excursion is taking place. What is anomalous is what suddenly changed to cause the geomagnetic field intensity drop to increase by a factor of 10 starting in the mid 1990s. Geological process happen on geological time scales.

There are a half dozen paradoxes associated with the planetary magnetic fields. I will provide background concerning the paradoxes in a few comments in this forum.

The following is a brief explanation of the 'standard' model and an explanation of one of the paradoxes.

The 'standard' (the word standard is not appropriate as there are known observational paradoxes that the standard model cannot explain, known paradoxes indicate there are fundamental errors in the standard model in question and perhaps indicate that the model its self is incorrect) geomagnetic model assumes the geomagnetic field is caused by a self generating dynamo where an initial magnetic field from unknown sources is maintained by the convection motion in the liquid core.

Convection motion requires a heat differential to drive convection. There is a heat differential created when a pot of water is placed on a hot element and brought to a boil. There is an insignificant heat differential if the boiling water is poured into an insulated flask to cause significant convection motion in the flask contented liquid.

The assumed heat differential to drive convection in the earth's liquid core is produced by the latent heat that is released when a portion of the liquid core solidifies at the liquid core/solid core boundary.

Basic direct measurement of heat flow from the deep earth and basic analysis indicates the solid core has existed for 800 million to at most a billion years. Without the liquid/solid core boundary there is no hot source to create a significant thermal differential. (When there was no solid core, the liquid core is hot and losing heat to the surface however there is a gradual temperature differential from the base of liquid core to the liquid core mantel interface and hence a factor of 10 less convection motion.) Calculations indicate that thermal motion drops by more than a factor of 10 without the liquid core/solid core boundary.

Now it is known that the earth magnetic field is more than 4 billion years old. Also calculations indicate the solar wind will strip off the majority of the water off the planet in about a 100 million to 200 million years if there was no magnetic field.

What I have described above is the heat flow paradox.
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Jul10-14, 10:57 AM
P: 40
The finding that the geomagnetic field intensity suddenly and cyclically drops by a factor of 5 to 10 was not expected and does not have an explanation.
Is the geodynamo process intrinsically unstable?
Recent palaeomagnetic studies suggest that excursions of the geomagnetic field, during which the intensity drops suddenly by a factor of 5 to 10 and the local direction changes dramatically, are more common than previously expected. The `normal' state of the geomagnetic field, dominated by an axial dipole, seems to be interrupted every 30 to 100 kyr; it may not therefore be as stable as we thought. We have investigated a possible mechanism for the instability of the geodynamo by calculating the critical Rayleigh number (Rc) for the onset of convection in a rotating spherical shell permeated by an imposed magnetic field with both toroidal and poloidal components.
Recent studies suggest that the Earth's magnetic field has fallen dramatically in magnitude and changed direction repeatedly since the last reversal 700 kyr ago (Langereis et al. 1997; Lund et al. 1998). These important results paint a rather different picture of the long-term behaviour of the field from the conventional one of a steady dipole reversing at random intervals: instead, the field appears to spend up to 20 per cent of its time in a weak, non-dipole state (Lund et al. 1998). One of us (Gubbins 1999) has suggested that this is evidence of a rapid natural timescale (500 yr) in the outer core, and that the magnetic field is usually prevented from reversing completely by the longer diffusion time of the inner core (2 to 5 kyr). This raises a number of important but difficult questions for geodynamo theory. How can the geomagnetic field change so rapidly and dramatically? Can slight variations of the geomagnetic field affect the dynamics of core convection significantly? If so, is the geodynamo process intrinsically unstable?
What Caused Recent Acceleration of the North Magnetic Pole Drift?
The north magnetic pole (NMP) is the point at the Earth’s surface where the geomagnetic field is directed vertically downward. It drifts in time as a result of core convection, which sustains the Earth’s main magnetic field through the geodynamo process. During the 1990s the NMP drift speed suddenly increased from 15 kilometers per year at the start of the decade to 55 kilometers per year by the decade’s end. This acceleration was all the more surprising given that the NMP drift speed had remained less than 15 kilometers per year over the previous 150 years of observation. Why did NMP drift accelerate in the 1990s? Answering this question may require revising a long-held assumption about processes in the core at the origin of fluctuations in the intensity and direction of the Earth’s magnetic field on decadal to secular time scales, and hints at the existence of a hidden plume rising within the core under the Arctic.
Jul10-14, 04:48 PM
P: 40
This an image from the Swarm satellite data that shows the South Atlantic geomagnetic anomaly where the geomagnetic field intensity has declined by 60%.

This is an image from the Swarm satellite data that shows how the geomagnetic field intensity has changed in six months.

This is a link to to Swarm information blog where the above images are found.

Aug16-14, 10:26 AM
P: 3
Swarm Data: Earth's Magnetic Field is Weakening 10 times Faster

This issue has been discussed extensively in general-interest science magazines such as Scientific American, as well as in popular science television programming such as on the Discovery Channel. For years scientists been doing computer simulations of the earth's core and the geomagnetic field. The whole system is largely chaotic. Wild and "unexpected" fluctuations are normal. Statistically speaking, the chances of such a fluctuation being a precursor of a geomagnetic reversal are pretty slim.

Incidentally, such reversals don't need to take 1000 years. They can happen in a few years. It can also flip right back to where it was within 2 or 3 years.

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