Aurora On The Move



A recent posting to the Pacific Northwest VHF Society's reflector brought my attention to an interesting article describing the southward migration of the auroral zone.




According to the research paper published in the Proceedings of the National Academy of Sciences, the earth's magnetic field is gradually growing weaker, thus affecting its interaction with the solar wind.

The paper indicates that our present, abnormally high magnetic field, forces this interaction (auroras) to higher latitudes and as the field strength gradually weakens to more long-term average levels, auroras will be seen further south than we have been used to. The field has already weakened by about 10% over the past two hundred years and will continue to do so. Apparently it's all related to the regular 'flipping' of our magnetic field, with the most 'recent' flip taking place about 780,000 years ago.

So what does this mean for radio amateurs? Probably not a lot, in the immediate future but the unwanted effects to disturbances in the geomagnetic field will eventually be felt further and further to the south. Radio propagation in southern British Columbia has always been particularly sensitive to even very small disturbances in the field, particularly on the LF and MF bands. I am constantly amazed at how regions only 150 miles to the south or southeast of me are so much less affected than here, in the southern fringes of the auroral zone. VE7's don't claim to be in radio's 'black hole' without good reason.

Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

Leave a Comment

Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter
News, Opinion, Giveaways & More!

E-mail 
Join over 7,000 subscribers!
We never share your e-mail address.



Also available via RSS feed, Twitter, and Facebook.


Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter

 
We never share your e-mail address.



Do you like to write?
Interesting project to share?
Helpful tips and ideas for other hams?

Submit an article and we will review it for publication on AmateurRadio.com!

Have a ham radio product or service?
Consider advertising on our site.

Are you a reporter covering ham radio?
Find ham radio experts for your story.

How to Set Up a Ham Radio Blog
Get started in less than 15 minutes!


  • Matt W1MST, Managing Editor




Sign up for our free
Amateur Radio Newsletter

Enter your e-mail address: