NYTimes: Will Compasses Point South?collapse of the Earth's magnetic field

[papau]

http://www.nytimes.com/2004/07/13/science/13magn.html?pagewanted=all



Will Compasses Point South?

July 13, 2004
Will Compasses Point South?
By WILLIAM J. BROAD

The collapse of the Earth's magnetic field, which both guards the planet and guides many of its creatures, appears to have started in earnest about 150 years ago. The field's strength has waned 10 to 15 percent, and the deterioration has accelerated of late, increasing debate over whether it portends a reversal of the lines of magnetic force that normally envelop the Earth.

During a reversal, the main field weakens, almost vanishes, then reappears with opposite polarity. Afterward, compass needles that normally point north would point south, and during the thousands of years of transition, much in the heavens and Earth would go askew.

A reversal could knock out power grids, hurt astronauts and satellites, widen atmospheric ozone holes, send polar auroras flashing to the equator and confuse birds, fish and migratory animals that rely on the steadiness of the magnetic field as a navigation aid. But experts said the repercussions would fall short of catastrophic, despite a few proclamations of doom and sketchy evidence of past links between field reversals and species extinctions.<snip>

Some experts suggest a reversal is overdue. "The fact that it's dropping so rapidly gives you pause," said Dr. John A. Tarduno, a professor of geophysics at the University of Rochester. "It looks like things we see in computer models of a reversal."<snip>


"It would be significant" in terms of planetary repercussions, he said in an interview, "but not catastrophic." High levels of ultraviolet radiation would spread down from polar regions as far south as Florida.<snip>


To better understand the current collapse, the European Space Agency plans to launch three satellites in 2009. The spacecraft, flying in polar orbits a few hundred miles up, are to map its intricacies until perhaps 2015.<snip>

[lanparty]

1. Thank Goodness for GPS ...

I can see why the Euros and Russians are deploying their own.

[muriel_volestrangler]

6. Well, sort of

Remeber that satellite electronics get affected by the weakening of the earth's magnetic field too.

If the trend really looks serious, it might mean that a new generation of more hardened satellites is needed. But there should be plenty of time for that - I don't think the new GPS systems will need take it into account yet.

[blackcat77]

2. Just to prevent any hysteria....

...the article emphasized that changes would take place over hundreds or thousands of years.

But it's a fascinating story and well worth the read.

[papau]

4. Agree-Glatzmaier model predicts multiple poles-new South Atlantic may be 1

Indeed the South Atlantic off of Africa zero field point is the most interesting part of the story!

The weakening currently under way may be a false alarm. The field often gets very weak, then bounces back, never having flipped.

In the 1980s, Gary Glatzmaier (University of California, Santa Cruz) and Paul Roberts (University of California, Los Angeles), began work on a computer model that by 1995 not only created a self-sustaining magnetic field (the first to do so), but after simulating the passage of 36,000 years, the field it generated spontaneously flipped.

[MikeG]

3. Damn, I'm going to have to buy a new BB gun with the compass in it.

[LastDemocratInSC]

8. You'll just shoot your other eye out

[prodigal_green]

5. so...what happens to NATO?

Does it suddenly become the South Atlantic Treaty Organization? Will the United States be a South American country? Up is down! East is West! Cats and Dogs are sleeping together (despite the Constitutional Amendment banning such behavior)

I had a geology professor in college who had a bumper sticker on his office door that said, "Stop Continental Drift!"

Just messing around...this is cool.

[LastDemocratInSC]

7. Here's another good bumper sticker along that same line ...

"Gravity isn't just a good idea - it's the law!"