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Ship Logs Suggest Upcoming Polar Reversal
Posted by
CowboyNeal
on Sat May 13, 2006 12:25 PM
from the straight-on-till-morning dept.
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!
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Global Warming? (Score:4, Funny)
Re:Global Warming? (Score:5, Funny)
Parent
Duh. (Score:5, Funny)
Just turn your compass around 180 degrees, then it'll be pointing South instead of North.
Re:Duh. (Score:5, Insightful)
While the flips may occur quickly on a geological timeframe, they take much longer than a human lifetime to occur and stabilize.
A compass is a handy thing to have at sea, since without landmarks its the easiest way to keep pointing in the same direction. But there are other ways to navigate - with and without technology. We (or rather, "they," since we'll long be dust) will just have to make do with them.
Parent
Re:Duh. (Score:4, Insightful)
While I doubt mariners will ever stop being taught compass and celestial navigation (tradition is important), I can't imagine either will be needed 100 years from now, much less a thousand.
Unless those statellites fall out of the sky, GPS is here to stay.
Parent
Re:Duh. (Score:5, Insightful)
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).
Not quite the same thing.
On land, it's easy to walk in a straight line. You pick a tree or a rock or a mountain, walk towards it, then check your GPS gizmo and it will tell you which direction you walked. But while you're walking, you simply walk in the direction of the landmark you've chosen.
At sea, this is impossible. You can't just steer towards a landmark, because there are none. The best you can do is steer towards a particular star (the sun counts), but you'll probably have to make corrections for its motion. A compass serves the same purpose as a distant tree or mountain on land -- keeps you pointing in the same direction over the course of the present to near future. You need to be able to do that reliably before position fixes can help get you where you want to be.
Position references can be finessed into giving you a bearing track, but that's like telling a day trader that because the stock went up yesterday it's going to go up again tomorrow - maybe, but maybe not. You need more data to be sure.
Parent
Re:Duh. (Score:5, Informative)
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.)
Parent
Re:Duh. (Score:5, Informative)
Parent
electronic dependence (Score:4, Insightful)
Re:electronic dependence (Score:5, Funny)
It won't affect my stereo because I'm using Monster
brand cables with a special anti polar reversal coating.
The extended warranty I was sold should keep it
functional for the 2000 years it takes to complete the process.
Man, Best Buy rocks!
Parent
long term effects (Score:4, Insightful)
Re:long term effects (Score:5, Funny)
I'm sure the biggest result of magnetic field reversal will be the number of PhDs granted.
Parent
Yei! (Score:5, Funny)
Let the War on Polar Reversal begin!
Imagine the customers.... (Score:5, Funny)
I think I saw this on the nature channel (Score:5, Funny)
"No need to fret?" Like hell. (Score:5, Interesting)
Sure, no need to fret. It's not like we haven't invested hundreds of years worth of technology and research based on magnetic reference points. Oh, wait...
Nathan
It's just... (Score:5, Funny)
Have you seen maps from 1590? (Score:5, Funny)
Cause for concern (Score:5, Funny)
I find it hard to believe that we shouldn't be concerned.
North will stay the same... (Score:5, Funny)
Need to Take Action Now (Score:4, Funny)
There's clearly a need to take action now. I'd better go clear my calendar, then I'll be prepared.
Memo to Self: Get stick on "N" and "S" labels for compass.
Re:Slightly off... (Score:5, Informative)
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.
Parent
Re:Slightly off... (Score:5, Interesting)
People living at high latitudes and on the equator or flying planes for a living already get quite a bit more proton radiation than everybody else. British Airways has monitored their flight crews for a couple of decades and found that, despite the higher exposure, life expectancy was higher and cancer rates lower.
Parent
Re:north = ? (Score:5, Informative)
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.
Parent
Re:north = ? (Score:5, Funny)
Parent