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post #15 of Old 01-29-2014
nolatom
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Re: Magnetic Variance

Quote:
Originally Posted by Dean101 View Post
That's a good way to remember it I guess! It would probably help me if I had an actual chart in front of me. The ones I have are TVA charts for Kentucky and Barkley lakes. No Roses!
Ah, then you can add Roses to the Whiskey for the True Virgins!! ;-)

okay, to get serious for a nanosecond, you can get the NOAA charts on line, which will get you a look at the Compass Roses:

NOAA's On-Line Chart Viewer

Look at one for, say, Massachusetts Bay, then one for say the Central Gulf of Mexico (such as here in New Orleans) and you'll see that there's considerable variation in the former and almost none in the latter (so down here we seldom use the jingle). It has to do with the location of the iron ore in the northern Canada islands compared to the location of the North Pole, or so I was told. From here, they almost line up, hence almost no variation. But from the Boston area in Mass Bay, those Canada islands are considerably to the left of the North Pole, and your variation (sometimes called Declination) is about 15 degrees West.

Last edited by nolatom; 01-29-2014 at 06:13 PM.
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