# Side column on pole shift **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [January 12, 2007, 8:16pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744 "2007-01-12T20:16:29Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Mathochist](https://avatars.discourse-cdn.com/v4/letter/m/c89c15/32.png) [@Mathochist](https://boards.straightdope.com/u/Mathochist)\ **Post date:** [January 12, 2007, 8:16pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/1 "2007-01-12T20:16:29Z")
Unca Cece deals with a few of the possible effects of a pole shift in [today’s column](http://www.straightdope.com/columns/070112.html). One of them is that magnetic compasses won’t be the most reliable instruments for a while. Bad news for boy scouts, but in this age of GPS who really uses the old compasses anymore? One thing I’m left wondering is how important the geomagnetic field really is to electrical systems. My understanding is that even now the field isn’t that strong. Could a shifting field really throw off the grid that badly? ---
**Author:** ![butler1850](https://avatars.discourse-cdn.com/v4/letter/b/779978/32.png) [@butler1850](https://boards.straightdope.com/u/butler1850)\ **Post date:** [January 12, 2007, 8:32pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/2 "2007-01-12T20:32:34Z")
[QUOTE=Mathochist] . Bad news for boy scouts, but in this age of GPS who really uses the old compasses anymore? [/QUOTE] Hunters, hikers. Why carry a GPS if you have a map & compass? If you can read a map, and use a compass, it’s a whole lot less gear to carry. If you know the woods well enough, just a compass works well enough. I can get a replacement compass for \<$10 and it never needs batteries (which WILL fail when you NEED them most.) Even if I had a GPS with me, I’d still have a compass with me as well for backup. Heck, I usually have a proper compass in my pack, and a [small pin on](http://store.everestgear.com/eqbrn164.html) one on my shirt/jacket. I use a compass in my car as well for taking "unknown ‘short cuts’ " ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [January 20, 2007, 10:01am UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/3 "2007-01-20T10:01:32Z")
[QUOTE=Mathochist] Unca Cece deals with a few of the possible effects of a pole shift in [today’s column](http://www.straightdope.com/columns/070112.html). One of them is that magnetic compasses won’t be the most reliable instruments for a while. Bad news for boy scouts, but in this age of GPS who really uses the old compasses anymore? [/QUOTE] Pilots, and by extension the general travelling public? Modern commercial aircraft with inertial navigation systems don’t need a compass for their intial setup, they can align with true north by measuring the topple of their internal gyros over time. However INS are heavy and expensive, smaller aircraft including regional turbo props still need to reference the Earth’s magnetic field to establish a heading reference. GPS does not give accurate near instantaneous heading information the way a gyro slaved to the Earth’s magnetic field can. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [January 20, 2007, 4:05pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/4 "2007-01-20T16:05:21Z")
[QUOTE=Mathochist] One thing I’m left wondering is how important the geomagnetic field really is to electrical systems. My understanding is that even now the field isn’t that strong. Could a shifting field really throw off the grid that badly? [/QUOTE] My understanding is not that the main effects would not necessarily be an overloading of the grid, but disruption of control systems and such resulting from increased levels of cosmic and magnetic radiation coming from the outside in, as well as the earth-bound effects. We know that solar flares and other activity from space can seriously disrupt radio communications, and several power outages have been blamed on solar flares (although this is an area of minor dispute). An example can be found here. From: [http://science.nasa.gov/headlines/y2003/12nov\_haywire.htm](http://science.nasa.gov/headlines/y2003/12nov_haywire.htm) > [@](#): > > The effects on Earth were many: Radio blackouts disrupted communications. Solar protons penetrated Earth’s upper atmosphere, exposing astronauts and some air travelers to radiation doses equal to a medical chest X-ray. Auroras appeared all over the world–in Florida, Texas, Australia and many other places where they are seldom seen. > > … > > “In 1989 a flare about half that strong caused a widespread power blackout in Quebec,” recalls Hathaway. Last week’s blast was aimed away from Earth, so its effects on our planet were slight–a bit of good luck. Looking forward, there is much speculation in the industry that wandering magnetic poles could induce huge currents in high-tension lines, causing overloads and blackouts in areas, or even leading to the need for permanent changes in line routing, such as if a pole sat right square on top of a major city. I don’t think people really know what’s going to happen, but they think whatever it is, it will be a pain in the ass. Like most things in life are… ---
**Author:** ![JKellyMap](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jkellymap/32/15880_2.png) [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)\ **Post date:** [January 20, 2007, 8:44pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/5 "2007-01-20T20:44:14Z")
[QUOTE=Mathochist] but in this age of GPS who really uses the old compasses anymore? [/QUOTE] Speleological cartographers, a.k.a. cave mappers. ---
**Author:** ![clayton\_e](https://avatars.discourse-cdn.com/v4/letter/c/c57346/32.png) [@clayton\_e](https://boards.straightdope.com/u/clayton_e)\ **Post date:** [January 20, 2007, 11:52pm UTC](https://boards.straightdope.com/t/side-column-on-pole-shift/387744/6 "2007-01-20T23:52:29Z")
A quote from the column article: > [@](#): > > **While the experts are vague on the details, they’re pretty sure the earth’s magnetic field is a result of movement in the planet’s liquid iron and nickel core** (although Jupiter and other planets believed to lack such cores also have magnetic fields). They also know the field isn’t stable and tends to shift in at least two different ways: the magnetic poles typically wander around slowly, but every so often flip completely, reversing the magnetic polarity of the planet. (bolding mine) I read the article the other day and didn’t recognize the above paragraph when I reread it today.. Especially the bolded sentence which I believe originally said “they just don’t know how it works”. Was it changed or am I just dillusional?