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Ship Logs Suggest Upcoming Polar Reversal

Posted by ryuzaki0 on from the straight-on-till-morning dept.

Nyerp writes "Researchers are using naval logs dating back as far as 1590 to arrive at better estimates of the decline of Earth's magnetic field. The results suggest that there may be a reversal of earth's magnetic field in about 2000 years." Also worth noting, our ancestors have lived through a number of polar reversals, and we're still here, so no need to fret!

4 of 349 comments (clear)

  1. Re:Slightly off... by 4D6963 · · Score: 4, Informative
    To say just because our ancestors lived through it 780 million years

    780 million years ago, there was nothing close to a monkey on earth. There wasn't even any ammonites IIRC. I think you mean 780,000 years ago.

    As for your skin cancer concern, I saw a show about the very topic of magnetic field reversal on TV about one year ago. They explained basically what this article explains about the field weakening and all that, and they answered to the question of whether cancers due to the the lack of a magnetic field would wipe all of us out of the surface of us, and the answer was that the number of cancers due to that wouldn't be that significant, however I forgot the estimates.

    --
    You just got troll'd!
  2. Re:north = ? by Anonymous Coward · · Score: 5, Informative

    Not entirely. There will actually be several poles.

    The Earth's magnetic field isn't just a dipole (2 pole) field. There are other components of the field, quadurpole (4 pole), octopole (8 pole), etc.. Normally, these components are at least on oder of magnitude weaker than the dipole component. During a magnetic field reversal, the dipole component is so weak that the other components become important. The Earth will then have several sets of weak magnetic poles, at various places around the Earth.

  3. Re:Duh. by Mostly+a+lurker · · Score: 4, Informative
    Like GPS (or the Euro version Galileo) and stars?

    No. Neither of those will tell you which way you're pointing. Both of those tell you where you are (actually, the cellestial version will only tell you where you are with the aid of an accurate clock).

    The stars, with even a rudimentary timepiece, are sufficient to provide a good guide to general direction. Before compasses ever existed, navigation was done based on them.

    As for GPS (the most accurate versions) two appliances at opposite ends of a vessel together with suitable calculations would give you the orientation of the vessel. (I have no idea if this is ever done.)

  4. Re:Duh. by Spy+Hunter · · Score: 4, Informative

    No need for two GPS receivers. If you are moving, the GPS can easily tell which direction you are going, which is more important than the direction you are facing anyway (especially on a boat or plane where they might be different without an easy way to tell).

    --
    main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}