Anyone else seen lots of recent news articles on this?
Is it as scary as some portray?
It's nothing, disregard it. The flip is due to happen within maybe the next 1,000 years. Hard to say. We've had a lot of threads about it in the Earth forum. I'll move this there.
Ugh. Evo is dead on. More journalism problems - mostly aimed at getting you click onto and read pages filled with ads.
Modern humans have done just fine, thank you, during recent pole flips and pole wandering. "Recent" in geology is a very long time time to us humans. Dating an archeological site using the orientation of iron's magnetic field in the remains of ancient cooking fires is based on the fact that we know when pole flips/meanders happened in the past. Google for archaeomagnetism.
You'll have to wear your tin-foil hat inside out.
Just today, there are more "calming" articles out.
Prior to the NatGeo article (which later on does show "some" potential concerns ... ), I'd seen some scary articles coming out in bunches.
"end of living species" ..."apocalypse" were some catch words.
I guess NatGeo is more science oriented and truthworthy?
I guess the good news is that not many technologies use magnetic needles for North-South navigating anymore. I think GPS is mostly what is used for that now...
The magnetic field flips fairly regularly over periods of 100,000s yrs, you can grossly date igneous rocks by their magnetic orientation. I don't think any mass extinction correlates to the time period a flip has happened, except maybe coincidentally. There is a risk of increased ambient radiation as the magnetic moment goes to 0 as it changes direction and then cosmic rays can more easily penetrate the atmosphere, but this transition happens over hundreds of years, so it isn't as if everything gets fried suddenly. I suppose species, such as of birds and insects, that use magnetic orientation for navigation will be confused, but overall life has gone through these events with very little effect overall according to the geologic record.
that's a bit of an "out there" generalisation for some of many flips
the periods between many flips can be measured in millions of years
tho it has been more regular in the last 20 - 25 million years
I cant get that page to load .... when did they say the last one or 2 flips occurred ?
for the last 160 million years
and for the last 5 million years ....
the last flip was 780,000 years ago
an article or so on time to flip .....
@davenn - they are not mentioning flips in the article - just pole meandering. The 780K pole flip does in fact post date the oldest known genus Homo cooking fire. I think.
Here is an example of the discussions based on Wrangham's 'Cooking Hypothesis':
IMO - archeology has been a contentious field, in the extreme. Example: A human coprolite (fossil poop) from a site dated to circa 1100 CE was found at Chaco National Historical Center in New Mexico (Chaco Canyon). It was tested to contain undigested human muscle proteins - myoglobin. It really hit the fan because nobody around here wanted to be the descendants of cannibals. Most vocal were PhD's in archeology. I'll see if I can find the reference - the original, not the storm of skepticism. A lot of older material is not online....
Best I can do:
Here is one about Cowboy Wash: https://en.wikipedia.org/wiki/Cowboy_Wash See the bit on cannibalism. Note the Ute (Indian tribe) position on the find.
More on the 'cooking hypothesis'. Humans can perceive very low levels of the product of the Maillard reaction:
Example: cereal grains -
It is very unusual to evolve specific abilities to smell essentially neutral compounds (as far as is known) that occur in minute quantities in foods. Except in the sense that we perceive the smell as really good - bread just out of the oven for example. This is construed as biochemical evidence of selection of humans for those who ate cooked foods.
Sorry for the digression....
And it shouldn't affect the use of a sextant, or celestial navigation techniques.
Don't say that to a mariner . We assume with good cause, that all those electronic gadgets will fail at the worst possible time. My compass, my tiller (no fancy wheel for me), and my mechanical self-steering are life vital equipment.
Four times when under way, I've seen my GPS lose a valid position solution for as short as 30 seconds and as long as 30 minutes. During those failures, the indicated position was wrong by 300 feet up to nearly 100 miles. Different GPS devices have different sensitivities, and better CPUs for iteration, so some may fail when others don't. Some GPS may also be smart enough to say "malfunction" rather than indicate a wrong position. Since we have unlimited number of GPS hardware & software vendors, we can't generalize.
Compasses are also required equipment on airplanes, although modern versions may include "magnetically stabilized direction indicator" or fluxgate. But modern or ancient, they are still "magnetic needles."
I remember joking with other sailors. If the magnetic poles did flip, would we republish all the maps so that Antarctica is north, or would we simply flip the definition of which end of that needle points north?
I'm still not clear about just what is going to happen. What exactly happens when the poles "flip"? Does the polar meander speed up until the magnetic poles are more-or-less reversed? .. or does the field turn off, then back on in the opposite direction? The implications for life on earth are very different as some have pointed out.
It is discussed in detail on Wikipedia
The wikipedia page also has this neat picture.
Interesting Quiz Question -- Calculate how much energy could be harvested by an Equatorial conductor (or coil) during the disturbance and flipping of the magnetic field. Bonus points for calculating the optimum number of turns for such an Equatorial conductor band...
Will the boy scouts get lost in the woods if their compasses no longer work? LOL.
Not if it takes 1000 years to flip.
Sailors have a simpler trick up their sleeve. Unless you are in the Arctic or Antarctic, and if you are lost: Just sail East or West and you must eventually find land.
I think today they all have GPS capability with their cell phones, unless they are outside an area that receives transmission.
Which they, the boy scouts? For sailors, see #12.
yes, generally accepted that they continue to wander and at some point during the flip, the N and S poles with be at the equator on opposite sides of the earth
I would deem that as pretty much impossible ... it's not like a solenoid across a battery with a switch that can be turned on and off
It has happened previously over the course of hundreds of thousands of years. The mechanism seems to be more readily obtained than reversing the magnetization of a permanent magnet. That requires either a very powerful external magnetic field or heating above the Curie temperature. The necessary geological processes apparently exist that can make this pole reversal occur, but I don't see it happening in our lifetime.
not sure why you specifically quoted me ?????
Just following the discussion. I replied to your post, and the quote was included with the reply. :)
sooooo .... didn't you like something in my post ?
I assume you didn't, else you wouldn't have quoted me
it would be nice if you didn't quote people unless you were specifically responding to something that person said
Separate names with a comma.