>
> Wow . . .
>
> Magnetic North Pole Shift Causes Tampa Runway to Close
> http://technology.gather.com/viewArticle.action?articleId=281474978886856
Below is my comment to that article. Background researching the other news articles upon which this post at gather.com was made, I found all of them hyped misrepresentations of natural and relatively well known processes. Plus as typical the FAA person interviewed was not an expert.
This is a slow process and runway redesignation happens all the time. Declination lines are published yearly and used to convert magnetic headings to true headings. Runway designations are basically the nearest 10 degrees, so once a normal declination passes the ±5° mark the runway name is changed e.g Runway 18 is aligned to magnetic north 180°±5 when it exceeds that window it is repainted and published on Aeronautical/Marine charts. The new runway name will be 19 I think but not looking at the map it could become runway 17.
This is non-news per se and the bulk of the news reports I've seen fail to understand the normalcy of the process. That said, we are over due for a pole reversal--magnetic pole nor true pole "wobble" has nothing to do with this--The Earth is not about to "flip over".
Magnetic pole reversals happen on the average of 100,000 years according to the paleo-record and we are well past that interval ( 360,000 since last reversal--some say 780,000?) We are seeing increasing occurrence of temporary multiple small "poles" were magnetic flux seems to converge. I think this spring there was a large on off the east coast of South America. Plus compass response to the main poles is dropping. Historically, we know that the reversals occur fairly rapidly over geological time (10s to 100s of years) and the poster is correct there will be a window of increased radiation reaching the surface during that wane of magnetic flux. Fortunately there is no evidence thus far of any extinction of species associated with past pole reversals.
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