Is the earth's magnetism decreasing?

AI Thread Summary
The discussion centers on the Earth's decreasing magnetism and its potential implications for humanity over the next thousand years. Participants acknowledge that the magnetic field has fluctuated historically, with expectations of a renewal process involving pole shifts. While some express concerns about the future, particularly regarding a complete loss of the magnetic field within 200 years, others suggest that such scenarios are unlikely and that the field will undergo various changes rather than a catastrophic collapse. Overall, the consensus is that while the magnetic field will continue to change, it is not expected to pose a significant threat to human life. Additional resources, including a related thread in Earth Sciences and a website dedicated to modeling these phenomena, are mentioned for further exploration of the topic.
bblly
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i saw an article the other night on public television of the Earth's decreasing magnetism. does anyone have an idea what is going to happen in the next thousand years to the Earth's "blanket"? i understand it will renew back, as it has many times in the past, although the poles will shift, but what will that mean to humanity?
of course no one is at threat born today even in a worst case senario, or are they? who knows? who has an idea? given evidence of the past, no major event on Earth has left life on Earth unaffected in some way.
 
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I heard that if it continues the way it has (but we don't know that it will), the field will be gone in 200 years. That is unlikely though, it will probably do all sorts of weird stuff. I have also heard from a psychic that it will collapse or move a lot or flip or something within a decade or so. So who knows.
 
You pretty much have it right, bblly. It'll decrease, flip, and increase again. It does that every now and then. And it won't do much to harm us.
 
There's a thread about it in Earth Sciences, and a link to a website by a guy who's trying to build a model; http://complex.umd.edu/dynamo/index.html , if you want to read more about it.
 
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