Not by Fire but by Ice


Discover What Killed the Dinosaurs . . . and Why it Could Soon Kill Us  

Magnetic Reversals and Glaciation


During highlighted magnetic reversals (or excursions), the climate descended from periods of warmth such as today's into full-blown glaciation in less than twenty years. (kya = thousands of years ago)


  • That there is a link between magnetic reversals and ice ages is undeniable.
  • At least twelve magnetic reversals can be linked to glaciation during the last three million years alone.
  • A magnetic reversal about three million years ago marked the onset of glaciation. A magnetic reversal about two million years ago marked the onset of glaciation. And yet another reversal about one million years ago marked the onset of glaciation.
  • The Jaramillo magnetic reversal maked the onset of glaciation, as did the Brunhes magnetic reversal.
  • The Biwa I, Biwa II, Biwa III, and Blake (at the end Eemian) magnetic reversals coincided with glaciation, and so did the Lake Mungo, Mono Lake, and Gothenburg magnetic reversals (or excursions).
  • Many of those catastrophic cooling episodes, says Michael Rampino of NASA, may have actually been triggered by the magnetic reversal (or excursion).

Why should this concern us?

  • One: We appear to be headed for another magnetic reversal right now. During the past 2000 years, magnetic field strength has fallen some 50 to 65 percent. Unfortunately, the rate of decline is picking up. Five percent of the decline has occurred during the last 100 years alone. This decline, say geophysicists, may be a precursor to a new reversal attempt.
  • Two: When ice ages begin, they begin incredibly fast. At the end Eemian, for example, the climate descended from a period of warmth such as today's - such as today's - into full-blown glacial severity in less than twenty years.
  • Three: I think we're headed into such a twenty-year period right now.
  • Four: The North Magnetic Pole is moving! "The magnetic pole, which has steadily drifted for decades, has picked up its pace in recent years and could exit Canadian territory as soon as 2004," said Larry Newitt of the Geological Survey of Canada. "It's speed has increased considerably during the past 25 years," the geophysicist said. See: - North Magnetic Pole - March 20, 2002.  

  • Five: According to John Tarduno, professor of geophysics at the Univerity of Rochester (NY), the next magnetic reversal could occur within a matter of centuries. 

    Tarduno based his findings on detailed studies of the Earth's magnetic field made during four trips above the Arctic Circle.  (Published in the Proc. of the National Academy of Sciences, 16 Oct 2002.) 

    As a press release from the University of Rochester puts it, Tarduno's findings "suggest that humanity is in for a surprise in the not-too-distant future. Since the Earth's magnetic field has been decreasing in intensity for the last several thousand years, and the intensity and likelihood of pole reversals are linked, in as little as a few centuries we may see the Earth's magnetic poles flip, sending everyone's compasses angling toward the South Pole."
Magnetic reversal may be in progress - BGS
17 Jan 11 - According to the British Geological Survey (BGS, we could now be headed into a magnetic reversal, thus validating the premise of Not by Fire but by Ice and Magnetic reversals and Evolutionary Leaps.
See Magnetic reversal may be in progress - BGS

Will compasses point south?
No, this headline doesn’t come from some supermarket tabloid, it comes from the New York Times and it backs up what I’ve been saying for years – that we are headed for a geomagnetic reversal.

Magnetic field strength has waned 10 to 15 percent over the past 150 years, the article says, and the deterioration has accelerated. “The fact that it (magnetic field strength) is dropping so rapidly gives you pause,” says Dr. John A. Tarduno, professor of geophysics at the University of Rochester. The odds of a reversal are “more likely than not,” says Tarduno. (New York Times, July 13, 2004, by William J. Broad)

The article goes on to say that the last magnetic reversal occurred some 780,000 years ago, and that there is no correlation between magnetic reversals and extinctions. 

I disagree with both of those contentions. I have evidence that there have been at least eleven magnetic reversals in the past 780,000 years - probably many more. I also have evidence that extinctions and reversals do in fact go hand-in-hand.
And I have evidence (from Steens Mountain in Oregon) that  magnetic reversals can take place in a mere 30 days. 

Ice ages also correlate with magnetic activity on the Sun.

According to Mukul Sharma, Assistant Professor of Earth Sciences at Dartmouth, the Sun displays a 100,000-year cycle of magnetic activity that corresponds to the Earth's ice age history.

Sharma's calculations suggest that when the Sun is magnetically more active, the Earth experiences a warmer climate, and vice versa, when the Sun is magnetically less active, there is a glacial period. Right now, the Earth is in an interglacial period (between ice ages). This is also a time of high solar activity.

This cycle appears to match the 100,000-year ice-age cycle first theorized by Milutin Milankovitch, which suggests that ice ages correspond to the cyclical varations in the Earth's orbit around the Sun. (Earth & Planetary Science Ltrs, Vol. 199, issues 3-4, June 10, 2002)

(One of the methods Sharma used to determine historic magnetic activity on the Sun was through the study of beryllium 10, which I thoroughly agree with. In fact, I mention beryllium 10 production several times in my book.)


Earth’s magnetic field fading
12 Dec 03. The strength of the Earth’s magnetic field
has declined ten percent 10% during the past 150 years,
says Jeremy Bloxham of Harvard University. This could
be the prelude to a geomagnetic reversal. (For anyone
who has read Not by Fire but by Ice, you know I’ve
been saying for years that we’re headed for a
geomagnetic reversal.)






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