News, Videos, and More from the City of Racine, the State of Wisconsin, the USA, & the World
Monday, July 20, 2020
Earth’s magnetic field may change faster than we thought – new research
The Earth’s magnetic field, generated 3,000km below our feet in the liquid iron core, is crucially important to life on our planet. It extends out into space, wrapping us in an electromagnetic blanket that shields the atmosphere and satellites from solar radiation.
Rapid changes of the magnetic field are of great interest because they represent the most extreme behaviour of the ocean of molten iron in the liquid core. By tying the observed changes to core processes, we can learn important information about an otherwise inaccessible region of our planet.
Historically, the fastest changes in Earth’s magnetic field have been associated with reversals, which occur at irregular intervals a few times every million years. But we discovered field changes that are much faster and more recent than any of the data associated with actual reversals.
Nowadays satellites help monitor changes in the field in both space and time, complemented by navigational records and ground-based observatories. This information reveals that changes in the modern field are rather ponderous, around a tenth of a degree per year. But, while we know that the field has existed for at least 3.5 billion years, we don’t know much about its behaviour prior to 400 years ago.
To track the ancient field, scientists analyse the magnetism recorded by sediments, lava flows and human-made artefacts. That’s because these materials contain microscopic magnetic grains that record the signature of Earth’s field at the time they cooled (for lavas) or were added to the landmass (for sediments). Sediment records from central Italy around the time of the last polarity reversal almost 800,000 years ago suggest relatively rapid field changes reaching one degree per year.
Such measurements, however, are extremely challenging, with results still being debated. For example, there are uncertainties in the process by which sediments acquire their magnetism.
PLEASE BE SURE TO READ OUR DISCLAIMER AT THE BOTTOM OF THE PAGE
This website exists for entertainment purposes only. The reader is responsible for discerning the validity of information posted here, be it fictional or based on real events or people. The content of posts on this site, including but not limited to links to other web sites, are the expressed opinion of the original poster and are in no way representative of or endorsed by the owners or administration of this website. The posts on this website are the opinion of the specific author and are not statements of advice, opinion, or factual information on behalf of the owner or administration of JT Irregulars. This site may contain adult content and if you feel you might be offended by such content, you should log off immediately.
Not all posts on this website are intended as truthful or factual assertion by their authors. Some users of this website are participating in internet role playing, with or without the use of an avatar. NO post on this website should be considered factual information on face value alone. Users are encouraged to USE DISCERNMENT and do their own follow up research while reading and posting on this website. JT Irregulars reserves the right to make changes to, corrections and/or remove entirely at any time posts made on this website without notice. In addition, JT Irregulars disclaims any and all liability for damages incurred directly or indirectly as a result of a post on this website.
This site is provided "as is" without warranty of any kind, either expressed or implied. You should not assume that this site is error-free or that it will be suitable for the particular purpose which you have in mind when using it. In no event shall JT Irregulars be liable for any special, incidental, indirect or consequential damages of any kind, or any damages whatsoever, including, without limitation, those resulting from loss of use, data or profits, whether or not advised of the possibility of damage, and on any theory of liability, arising out of or in connection with the use or performance of this site or other documents which are referenced by or linked to this site.
Some events depicted in certain posting and threads on this website may be fictitious and any similarity to any person living or dead is merely coincidental. Some other articles may be based on actual events but which in certain cases incidents, characters and timelines have been changed for dramatic purposes. Certain characters may be composites, or entirely fictitious. We do not discriminate against the mentally ill!
Administrators may close an account, remove any post or comment and cancel author accounts as they, alone, deem necessary. You may contact the administration at email@example.com to report inappropriate use or to ask for the removal of specific material. The administration retains the final decision of what content constitutes appropriate use and what content is displayed.
Fair Use Notice: This site may contain copyrighted material the use of which has not always been specifically authorized by the copyright owner. Users may make such material available in an effort to advance awareness and understanding of issues relating to civil rights, economics, individual rights, international affairs, liberty, science & technology, etc. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C.Section 107, the material on this site is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes.