In November 2003, PBS
television presented a special on magnetic storms on
its program NOVA. This programmed
focused on the declining state of earth’s
magnetic field, the coming magnetic pole shift, and
its potential impact on life on earth.
"But now scientists have made
a startling discovery. It seems there's a storm brewing
deep within the Earth, a storm that is weakening our
vital magnetic shield".
PETER OLSON
(Johns Hopkins University): The Earth's magnetic
field has been our protector for millennia, and now,
it appears, it's about to go away.
JOHN SHAW
(University of Liverpool): The Earth's magnet
field is getting weaker rapidly.
MARIO ACUNA
(NASA Goddard Space Flight Center): We cannot
guarantee that the magnetic field of the Earth is still
going to be there a thousand years from today.
NARRATOR: Is our invisible
shield about to disappear?
JEREMY BLOXHAM
(Harvard University): The question is not if
that's going to happen, it's when that's going to happen.
NARRATOR: Could the Earth
really lose its magnetic field? And what will happen
if it does?
NARRATOR: No one has ever
experienced a magnetic reversal. If this is really the
beginning of a flip, what exactly will happen next?
"One man who may know, is geologist
Rob Coe. For 25 years, he's been coming to Steens Mountain
in Oregon, a vast heap of hundreds of ancient lava flows".
ROB COE
(University of California, Santa Cruz): Sixteen
million years ago there was a huge series of eruptions
here. You can pick out literally hundreds of lava flows
over on that wall. Each line delineates a different
lava flow. It's over 3,000 feet of overlying flows.
NARRATOR: What makes Steens
special, is that 16 million years ago, when this lava
was erupted, the magnetic field was in the middle of
a flip. Taking samples from dozens of flows all the
way up the mountain, Rob and his colleagues have pieced
together a detailed record of this magnetic reversal,
although it's so surprising that not everyone accepts
it.
ROB COE: What we found as
it started to reverse was the strength of the Earth's
field decreased dramatically, by 80 or 90 percent.
NARRATOR: The field started
out pointing south, but as it weakened the direction
of the field began to change erratically. After 300
years, it had swung a full 180 degrees to point north,
and the field strength started to recover.
ROB COE: But it couldn't hold
that polarity, and it fell back to...reversed and the
intensity crashed again.
NARRATOR: Once more the Earth's
magnetic shield practically disappeared, this time for
3,000 years. What was left was changing so fast that
Rob found a flow that captured these wild gyrations
even as the lava cooled.
ROB COE: And what we found
was even harder to believe. The quickly chilled margins
in the bottom and the top had one direction, like that
of the underlying flow, and the middle portion had a
direction that was sixty degrees farther away. It was
just as though, while the flow cooled, the field had
moved sixty degrees, which if you calculate it out,
that comes to about six degrees of movement per day.
If we were observing this with a compass, you would
be able almost to see the motion with your eye. It was
truly astonishing and extraordinary.
The fact that the magnetic shift could happen as rapidly
as six degrees per day indicates that the final phase
of a flip can happen in about one month’s time.
This is a good reason to examine the possibilities and
produce a reasonable hypothesis as to why such magnetic
changes could occur in the foreseeable future.
Is the Earth's magnetic field
reversing now? How do we know?
Measurements have been made of the Earth's
magnetic field more or less continuously since about
1840. Some measurements even go back to the 1500s, for
example at Greenwich in London.
If we look at the trend in the strength of the magnetic
field over this time (for example the so-called 'dipole
moment' shown in the graph below) we can see a downward
trend. Indeed projecting this forward in time would
suggest zero dipole moment in about 1500-1600 years
time. This is one reason why some people believe the
field may be in the early stages of a reversal. We also
know from studies of the magnetization of minerals in
ancient clay pots that the Earth's
magnetic field was approximately twice as strong in
Roman times as it is now.
This report is written with the intention of alerting
everyone to a potential danger to our biosphere on earth.
The proper action to take is to prepare for disaster
on a global scale and stop our petty wars. We need to
network and organize people to prepare earth ARKs for
the survival of humanity and civilization in the near
future.
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