New user here, first-time post; actually came for an entirely different topic, but I'll throw down my two cents on this somewhat outdated thread.
I flew a mission called the Space Experiments Support Package; a sun-sync LEO primary concerned with mapping the near earth magnetic, radiation, and
ionic environment. Needless to say, the SAA was of significant interest and impact. We called it the 'SAMA' (South Atlantic Magnetic Anomaly), and
so did NASA at the time - although 'Magnetic' fell out of favor owing to evolving theories.
Besides its scientific value, I can tell you it was a real PITA for the operators, since it often messed up a lot of things (instruments, cals,
measurements, etc.) at least four times a day: two consecutive passes ascending, then later two descending. While the community had been aware of the
SAA well before the mission ever launched (Wiki says 1958), the experimenters didn't realize it would cause as much of an impact as it did. After a
while, we figured out how to enter a pre-canned series of stored commands to reset stuff every time we passed through. Worked pretty well, but since
we only had 4K of memory (early 70's technology), it cramped our style a bit. And, a few of the instruments got fried early on.
While I don't purport to be either a geophysicist or an ET theorist, it seems WAAAYYY less than plausible that this could be man-made. That would be
on the scale of massive planetary engineering, and altering the inner-core (as opposed to the surface) at that.
It never seemed satisfactory to me that the effect is caused solely by - as Wiki puts it - the 'non-concentricity of the Earth and its magnetic
field' - i.e., the center of the magnetic dipole being offset from the center of mass. If that were true, wouldn't we see a stronger magnetic field
opposite the SAA? After having watched the data for years, I can assure you we don't. Nor can I entirely accept that the Van Allen Inner is simply
'closer to the earth' at the SAA than anywhere else. This discrepancy in the explanation is alluded to in the 'Singapore' portion of the Wiki
explanation, and has been referred to by some as the 'Singapore Sling' Theory.
The mere fact that the Earth's magnetic axis is a) titled 11 degrees off the spin axis; and b) wanders from year to year; would tend to indicate the
inner core is non-uniform - as if there is perhaps a big chunk of something
inside different from the rest of the molten iron - although this
cannot borne out by variations in the gravitational field. And yes, there are daily and annual variations in the shape and intensity of the SAA, but
that can be fairly easily explained by the solar wind.
So what it is then? I suggest this may be a (quasi-spherical) vortex of iron inside the core, kinda-sorta analogous to the Great Red Spot on Jupiter,
or a hurricane here on Earth, only on the inside. Our Sun exhibits similar phenomena, with wildly complex flux variations that wrap, warp, converge,
diverge, and ultimately 'snap', releasing massive outbursts of both energy and particles - CME's and solar flares - taking out the power grid in
Ontario, Dresden, or Buenos Aires every few decades.
Of course, we could postulate that advanced-race-type visitors deliberately engineered this eons ago, creating a homing beacon, an underwater-landing
worm hole, or a launch-boost mechanism, but like I said, I'm not an ET theorist, so I don't roll that way.
It is intriguing to propose that we could take advantage of the SAA by utilizing the extra energy in this region, but I'm not sure we have the proper
technology to do that just yet.
I'm still waiting for the poles to flip so we won't have to worry about it anymore. j/k.