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Posted on 04/10/2002 2:33:45 PM PDT by aculeus
Lots of misconceptions flying around. I'll just use the shotgun approach and hope I hit everything.
First, the planet is not going to go for a tumble. The magnetic poles flip at regular intervals, but we don't see geological evidence for cataclysmic upheavals happening at regular intervals.
Second, the way the water spirals out of your sink has nothing whatsoever to do with the magnetic field of the Earth, and very little even to do with the way the Earth is spinning. There is a Coriolis force caused by the Earth's rotation that has a slight effect on how your sink water behaves, but that effect is small compared to the way your sink is shaped and the direction your faucet points.
Third, the Earth's magnetosphere does not protect us very much against radiation (cosmic or solar). It does funnel solar radiation down to the poles, along with the lower-energy cosmic radiation. The higher-energy cosmic radiation punches right through. All of it hits the atmosphere. The low energy stuff gets absorbed, while the high energy stuff does reach the ground. (That's a whole topic in and of itself; do a Google search for "extensive air showers" before I really wax prolix.)
As further evidence, consider this. The Earth's magnetic field doesn't really deflect ionizing particle radiation so much as redirect it and funnel it all down towards the poles. If radiation from space were really that dangerous for people on the ground, then that effect would be greatly magnified at the poles: someone standing at the South Pole, for example, would get a great deal more radiation than would the average person in the absence of a magnetic field. In reality, it's only slightly higher, and that is dominated by the relative thinness of the atmosphere, I believe.
(Note: astronauts in low Earth orbit will have a serious problem with radiation if the Earth's magnetic field goes away.)
Fourth, ionizing radiation (i.e., that which can be deflected by the Earth's magnetic field) doesn't cause skin cancer. Ultraviolet light from the sun causes skin cancer, but that, of course, is not affected by the Earth's magnetic field.
Fifth, vannrox has been hanging out with medved too long.
ROFL ! ooooh nooooo our planet is wandering directionless in a liberal haze of mediocraty?
Guest: Robert Felix
"Beginning with the dinosaur extinction of 65 million years ago, Robert Felix explores the relationship between mass extinctions, ice ages, and magnetic reversals (times when compasses would have pointed south instead of north)."
from artbell.com website
http://www.geolab.nrcan.gc.ca/geomag/northpole_e.shtml
North Magnetic Pole
The Earth's magnetic field is shaped approximately like that of a bar magnet and, like a magnet, it has two magnetic poles, one in the Canadian arctic, referred to as the North Magnetic Pole, and one off the coast of Antarctica, south of Australia, referred to as the South Magnetic Pole. At the North Magnetic Pole the Earth's magnetic field is directed vertically downward relative to the Earth's surface. Consequently, magnetic dip, or inclination is 90° . In addition, the North Magnetic Pole is the eventual destination for a traveller who follows his or her compass needle from anywhere on Earth.
The North Magnetic Pole is slowly drifting across the Canadian Arctic. The Geological Survey of Canada keeps track of this motion by periodically carrying out magnetic surveys to redetermine the Pole's location. The most recent survey, completed in May, 2001, determined an updated position for the Pole and established that it is moving approximately northwest at 40 km per year. The observed position for 2001and estimated positions for 2002 to 2005 are given in the table.
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