NHNE News List
Current Members: 753
Subscribe/unsubscribe/archive info at the bottom of this message.

------------

Thanks to Jordan Wagner.

------------

SUN'S RAYS TO ROAST EARTH AS POLES FLIP
By Robin McKie, Science Editor
The Observer
Sunday, November 10, 2002

http://www.observer.co.uk/international/story/0,6903,837058,00.html

Earth's magnetic field -- the force that protects us from deadly radiation
bursts from outer space -- is weakening dramatically.

Scientists have discovered that its strength has dropped precipitously over
the past two centuries and could disappear over the next 1,000 years.

The effects could be catastrophic. Powerful radiation bursts, which normally
never touch the atmosphere, would heat up its upper layers, triggering
climatic disruption. Navigation and communication satellites, Earth's eyes
and ears, would be destroyed and migrating animals left unable to navigate.

'Earth's magnetic field has disappeared many times before -- as a prelude to
our magnetic poles flipping over, when north becomes south and vice versa,'
said Dr Alan Thomson of the British Geological Survey in Edinburgh.

'Reversals happen every 250,000 years or so, and as there has not been one
for almost a million years, we are due one soon.'

For more than 100 years, scientists have noted the strength of Earth's
magnetic field has been declining, but have disagreed about interpretations.
Some said its drop was a precursor to reversal, others argued it merely
indicated some temporary variation in field strength has been occurring.

But now Gauthier Hulot of the Paris Geophysical Institute has discovered
Earth's magnetic field seems to be disappearing most alarmingly near the
poles, a clear sign that a flip may soon take place.

Using satellite measurements of field variations over the past 20 years,
Hulot plotted the currents of molten iron that generate Earth's magnetism
deep underground and spotted huge whorls near the poles.

Hulot believes these vortices rotate in a direction that reinforces a
reverse magnetic field, and as they grow and proliferate these eddies will
weaken the dominant field: the first steps toward a new polarity, he says.

And as Scientific American reports this week, this interpretation has now
been backed up by computer simulation studies.

How long a reversal might last is a matter of scientific controversy,
however. Records of past events, embedded in iron minerals in ancient lava
beds, show some can last for thousands of years -- during which time the
planet will have been exposed to batterings from solar radiation. On the
other hand, other researchers say some flips may have lasted only a few
weeks.

Exactly what will happen when Earth's magnetic field disappears prior to its
re-emergence in a reversed orientation is also difficult to assess.
Compasses would point to the wrong pole -- a minor inconvenience. More
importantly, low-orbiting satellites would be exposed to electromagnetic
batterings, wrecking them.

In addition, many species of migrating animals and birds -- from swallows to
wildebeests -- rely on innate abilities to track Earth's magnetic field.
Their fates are impossible to gauge.

As to humans, our greatest risk would come from intense solar radiation
bursts. Normally these are contained by the planet's magnetic field in
space. However, if it disappears, particle storms will start to batter the
atmosphere.

'These solar particles can have profound effects,' said Dr Paul Murdin, of
the Institute of Astronomy, Cambridge. 'On Mars, when its magnetic field
failed permanently billions of years ago, it led to its atmosphere being
boiled off. On Earth, it will heat up the upper atmosphere and send ripples
round the world with enormous, unpredictable effects on the climate.'

It is unlikely that humans could do much. Burrowing thousands of miles into
solid rock to set things right would stretch the technological prowess of
our descendants to bursting point, though such limitations do not worry film
scriptwriters. Paramount's latest sci-fi thriller, The Core
(http://www.thecoremovie.com/) -- directed by Englishman Jon Amiel, and
starring Hilary Swank and Aaron Eckhart -- depicts a world beset by just
such a polar reversal, with radiation sweeping the planet.

The solution, according to the film, to be released next year, involves
scientists drilling into Earth's mantle to set off a nuclear blast that will
halt the reversal.

Given that temperatures at such depths rival those of the Sun's surface,
such a task would seem impossible -- except, of course, in Hollywood.

------------

PREVIOUS NHNE NEWS LIST ARTICLES:

EARTH'S MAGNETIC FIELD ABOUT TO FLIP? (7/8/2002):
http://groups.yahoo.com/group/nhnenews/message/3376

------------

NHNE News List:

To subscribe, send a message to:
nhnenews-subscribe@yahoogroups.com

To unsubscribe, send a message to:
nhnenews-unsubscribe@yahoogroups.com

To review current posts:
http://groups.yahoo.com/group/nhnenews/messages

Published by NewHeavenNewEarth (NHNE)
eMail: nhne@...
NHNE Website: http://www.nhne.com/
Phone: (928) 282-6120
Fax: (815) 346-1492

Appreciate what we are doing?
You can say so with a tax-deductible donation:
http://www.nhne.com/main/donations.html

P.O. Box 2242
Sedona, AZ 86339