[time-nuts] Re: The SI second and the ease of realization (was: leap seconds finally being retired?)

[Demetrios Matsakis]

Glacial rebound makes the Earth turn faster all by itself.  As the arctic goes up vertically, the equatorial regions have to go down and this makes the Earth rounder.   To conserve angular momentum, there is a speed up.  But a recent paper by Zotov et al says recent global warming will only speed up the Earth at 5% the rate we are seeing it.  It is ASR 69, Issue 1, January 2022, pp 308-313.

I guess we should avoid building optical frequency standards in Hawaii, as it moves much faster.  Not to mention Mauna Loa.

I was very impressed by a PTTI paper by Wolf,  late 90’s, which detailed a whole host of relativistic effects that kick in at 10^-18.  I don’t think he had continental drift in there though :)

> On Nov 29, 2022, at 2:59 AM, Poul-Henning Kamp via time-nuts <time-nuts at lists.febo.com> wrote:
> 
> --------
> Jürgen Appel via time-nuts writes:
> 
>> Another fun-fact for all time-nerds on the other side of the Atlantic trying
>> to do the intercontinental version of this experiment:
>> The Doppler-red-shift due to continental drift of ~1cm/year is of the same
>> order of magnitude: (1 cm / year)/c = 10^-18 as well.
> 
> Not to mention uplift from the most recent glaciation.
> 
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