the link doesn't work for me but "magnetic north", quite different than the axis north pole or "true north" has been shifting since the earth came into existance, jeannie. magnetic variation is an error that must be corrected in order to navigate with a compass. this deviation error is more or less pronounced depending on where on the planet you are when you look at a compass. one could stand on the actual north pole and his compass would indicate that to reach the "magnetic north pole" you would head south. your compass would read north but magnetic north is south of the north pole. weird or what? lol. even weirder is that from the true north pole, every direction is south. but that doesn't address the issue. just interesting to think about.

anyway, isogonic lines are drawn on maps used for navigating to indicate this compass deviation and only when positioned on the agonic line, or line of zero variation, will a compass point directly to true north, again assuming you are not positioned between magnetic north and true north at the north pole. air navigation charts are updated regularly partly because magnetic north is constantly shifting in relation to true north.

that worked. yes, runway renumbering does seem to be more frequent in the last few years. the faa issued a notam [notice to airmen] a few years ago for pilots to stay abreast of the situation. nothing new. but you asked if our compasses have been changing and the answer is no they haven't changed in the least. they always point to magnetic north. wherever that may be today. lol.

So its moving 40 miles a year... If you live 3,000 miles away from the pole, then you are looking at the angle whose tangent is 40/3,000...thats a very small angle.

In the scale of geological time, its fast!

And when it comes to using directions for orienteering, sailing, flying, etc, small angles really matter!

But as far as looking at your compass and seeing how much its changed in the last year - its not going to be very much.

I thought he might have meant 'reversed' instead of 'shifted'.

Maybe in the last year, but I am 62 years old and if memory serves me well, I remember when it used to point to north on the compass and now it points a bit north east. Like if north is 12:00 on a clock, the compass, where I am, points to 1:00.

Now if Denver is North and I was walking and I followed this compass I would miss Denver by a long shot going in that direction.

I know it "says" north, but north ain't the same as it used to be.

JB- if you started from say Central America and attempted to go 'north' to Denver using only a compass for navigation... You would miss it every time. (even with out the pole shift of more recent times).

You must also know the 'magnetic deviation' for your area. (which can vary a lot from place to place depending upon the 'local' magnetic field as well as the fact that earths magnetic field rarely 'lines up' with the actual spin axis).

btw, jb, the compass has never pointed directly true north from all points on the planet. not in the sixty two years you've lived nor ever.

JB- if you started from say Central America and attempted to go 'north' to Denver using only a compass for navigation... You would miss it every time. (even with out the pole shift of more recent times).

a compass will always point to MAGNETIC north, conrad. not to TRUE north. in fact a magnetic compass is all but useless for navigating the extreme northern latitudes. with the invention of gps and other lrn systems, the mag compass is pretty much useless anywhere anymore.