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▲ defrost 20 hours ago

Magnetic, rotational, geodetic .. ?

What are you trying to say?

▲sampo 17 hours ago | parent | next [-]

> What are you trying to say?

Perhaps https://en.wikipedia.org/wiki/Cataclysmic_pole_shift_hypothe...

▲defrost 5 hours ago | parent [-]

Might as well throw in the risk of being wiped out by a comet.

Climate risks are greater and more immediate than either comets or poles shifting.

▲falcor84 20 hours ago | parent | prev [-]

Can there even be geodetic drift of the poles? I sort of assumed that our lat/lon system is based on the poles being fixed points as a matter of definition.

▲defrost 19 hours ago | parent [-]

Each ellipsoid is rigidly defined (well, some historic ones are sloppy), so WGS84 won't drift .. (that's a bold statement, is it true down to the micron and if so what are the absolute* datums to reference against?).

That said, there are literally hundreds of historic pre WGS84 ellipsoid|datum pairings, each with a somewhat different "survey map pole".

Historically geodectic poles have shifted as a function of datums.

The main point here, such as it is, was to poke at the infomation free aspect of "polar drift" as a comment .. which pole and what does that have to do with climate change? etc.

▲avianlyric 16 hours ago | parent [-]

We still use many of those old ellipsis and datum’s today. When you’re doing human things, like surveying land, and defining property boundaries. It’s nice to work with a coordinate system which remains fixed relative to the area you’re surveying, and doesn’t drift due to annoying things like tectonic movement, or your entire country slowly tipping into the ocean.

▲defrost 5 hours ago | parent [-]

FWiW I'm old enough to have navigated via LORAN and travelled through over two thirds of the 190+ countries on the planet tying in multitudes of old datums to the "new" WGS84 standard as part of a career in geophysical surveying (Gravimetrics, tides, magnetics, radiometrics, EM, etc.)

I'm not old enough to have seen Great Britain and relate isles pressed down by the weight of kilometres of ice though .. that'd be a great great great grand something that saw that.