December 11, 2018 | David F. Coppedge

Earth’s Magnetic Field Decaying at an Alarming Rate

The biosphere depends on earth’s magnetic field, but it has been decaying rapidly for at least 1500 years.

In Spacecraft Earth: A Guide for Passengers, Dr Henry Richter describes how the story of the decay of the earth’s magnetic field caught his attention. He had read the monograph by Dr Thomas Barnes in the 1970s, and realized the implications: if the decay is true, the earth could not be billions of years old. He considered the various proposals for maintaining the field, but none of them work, he concluded. If this is a well-known fact, what do secular geophysicists have to say about it?

In chapter 7, Dr Richter discusses the implications of a decaying magnetic field.

Here’s the short answer, with details below: they are worried about it! They acknowledge the rapid decay, but have no theory to keep it strong enough for millions or billions of years. All they can do is watch it decay, and monitor changes in direction of the weakest spot over time. But unless they can model how it would get stronger again, life is in heap big trouble! Now, the details.

A new paper in PNAS, and a Commentary about it by John Tarduno in the same issue of PNAS, provide an up-to-date look at the problem from the secular long-ages viewpoint. Basically, in the first paper, Trindade et al studied stalactites in a South American cave looking for clues to variations in the geomagnetic field. Secular geophysicists have identified a “South Atlantic Anomaly” (SAA) in geomagnetic measurements, “the position of the weakest geomagnetic field on Earth.” They suspected that variations in the SAA might have been recorded in the speleothem data. Here’s what they say about their work. Notice that they acknowledge a “fast decay” the magnetic field’s strength.

Experimental and modeling evidence demonstrate the recurrence of the South Atlantic Anomaly. The areal growth of this geomagnetic anomaly accompanies the fast decay of the Earth’s magnetic field, but its origin and longevity are still poorly understood given the scarcity of geomagnetic data in the Southern Hemisphere. We report a ∼1500-y record with unprecedented resolution obtained close to the present-day minimum of the anomaly in South America from continuously grown cave speleothems. This unique record reveals rapid variations in direction and intensity of the local field as a function of the location and magnitude of the anomaly. Synthetic secular variation models show this feature may result from westward migration, expansion, and intensification of reversed flux patches on the core–mantle boundary.

To Dr Richter, these data are distractions from the main point: is the earth’s global magnetic field really on a downward trend? Small variations in one continental area won’t fix that. Without a mechanism to replenish the field strength, it will continue to decline, with dire consequences for life. Note that we are not talking about reversals in the field’s polarity (north vs south poles), nor about changes to the magnetic pole angle, but about field intensity or overall strength. Let’s look through these two papers for responses to that main issue.

How reliable are the measurements of decline?

We know much about the recent waning geomagnetic field; since the time of Gauss in 1840, we have had a rich data source in the form of geomagnetic observatory records. In the satellite era, we have a deluge of data from magnetometers in orbit. [Tarduno]

Here, we report a unique geomagnetic record for the last ∼1500 y that combines the data of two well-dated stalagmites from Pau d’Alho cave, located close to the present-day minimum of the anomaly in central South America. Magnetic directions and relative paleointensity data for both stalagmites are generally consistent and agree with historical data from the last 500 y. [Trindade et al]

In short, the new measurements agree with field decay further back in time.

Are any reversals of the decline indicated in the measurements?

These records indicate that the size of the anomaly has increased concomitant with increasing prominence (i.e., ever-weakening field intensity), and the anomaly has migrated continuously westward at a mean longitudinal speed of 0.17° y−1. Areal growth and intensity decay are linked to the first-order variations of the geomagnetic field, more specifically, the relative increase of nondipole terms relative to the overall field geometry and the steady decay in the dipole moment itself at a rate of ∼15 nT y−1. [Trindade et al]

The field is invisible to our senses, but allows life to exist.

Because a Tesla of magnetism is a huge value, a nanoTesla (nT) is not insignificant. This decay continues year after year. Over the 130 years of annual measurements begun by Karl Friedrich Gauss up through the monograph by Thomas Barnes, the field strength had decreased by 5%. That is a shocking amount of decay for such a brief time, which represents a mere flash in the assumed 4.5-billion-year-age of the earth that secularists treat as fact.

Are any theories available to reverse the decay in the past before actual measurements began?

The tracking of RFPs [reverse flux patches] throughout the last 3000 y using the available geomagnetic field models attests to the recurrence of reverse patches at specific regions and supports the hypothesis that links them to mantle heterogeneities, but when kernel functions that link the location of reverse patches at depth to the location of the anomalies at the planet’s surface are considered, a straightforward link between these features and the SAA has not been be [sic] established. [Trindade et al]

The results of Trindade et al. highlight the potential for further tracing of field behavior associated with the SAA back in time and space to discriminate between far-reaching but differing viewpoints on the nature of the geodynamo. In one interpretation, reversed flux patches are purely intrinsic to the flow of iron in the core, without any influence of the overlying mantle. Hence, the occurrence of flux expulsion, reversed flux patches, and other anomalous features such as field-strength spikes or high secular variation would not have any geographic preference. Reversals should also not nucleate in any preferred location beneath the mantle. In contrast, in the top-down hypothesis, the core–mantle boundary stimulates flux expulsion and formation of reversed flux patches, and this could occasionally lead to a field reversal. In yet another interpretation, a bottom-up control on the geodynamo driven by the interaction of the inner core with the fluid outer core could also lead to geographic preferences in geomagnetic field behavior departing from that of a simple dipole.

The tracking of anomalies denoted by Trindade et al. gives a nod to top-down control of the geodynamo, but more data will be needed before the community can fully evaluate these viewpoints and better parse the related processes. [Tarduno]

What are the consequences of continuing field decay?

The South Atlantic Anomaly (SAA) marks the position of the weakest geomagnetic field on Earth, and has long been recognized as a major sink for high-energy particles in the magnetosphere, with consequences for orbiting satellites, as well as telecommunication networks and transmission grids. [Trindade et al]

Irrespective of the details of that outcome, the recurrence of changes documented by Trindade et al. provides motivation to use the past as a guide to the future. The nadir of the last occurrence of low intensity recorded in the Limpopo and efforts to forecast the field give us reason to believe that the global field-intensity decay will continue in the coming century. This should be a call to arms to further improve the resiliency of satellites and infrastructure as our planetary magnetic shield becomes ever more imperfect. [Tarduno]

None of these scientists mentioned the consequences for life, but clearly the earth’s magnetic field is extremely important for protecting the biosphere from the high-energy charged particles that would otherwise bombard the planet. The beneficial protective effect of our magnetic field is shown in Illustra Media’s new short film Heavenly Fire, which can be viewed for free at

Earth is constantly bombarded by deadly radiation from the sun, but the magnetic field defends us from most of the dangerous particles. (Illustra Media)

Dr Richter’s book concentrates on design arguments, but in chapter 7, he discusses evidence that the earth cannot be as old as evolutionists claim. His primary evidence is the decay of the earth’s magnetic field. Here, you have seen moyboy geophysicists with a prime opportunity to put forth an explanation for how the magnetic field could be millions and billions of years old. They couldn’t do it. They trust in their radiometric dating methods, but they acknowledged openly that the magnetic field is decaying “at an alarming rate,” that it’s probably going to continue to decay (using “the past as a guide to the future”), and the consequences are dire. Dr Richter shows how the decay rate, if extrapolated into the past as an increase back in time, quickly becomes so high that life would be impossible in just 20,000 years. The earth, therefore, cannot be millions of years old.

Add to this the completely separate evidence for a young earth implicated by geneticist Dr John Sanford in his talk to the NIH (16 Nov 2018). If the human population cannot avoid extinction in the near future from mutational meltdown, neither could it have endured millions of years of mutations in the past. These are only two evidences that rule out millions of years, and there are many more.

For those Christians who denounce Darwin but still think we must give secular scientists their millions of years, please take a serious look at this evidence. You don’t want to be anti-science now, do you?

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