[LEAPSECS] Never mind DUT1, what's up with dX and dY

[Steve Allen]

On Mon 2024-01-08T11:40:11+0000 Poul-Henning Kamp hath writ:
> When I look at the Bulletin-A plots at IERS:
>
>       https://www.iers.org/IERS/EN/DataProducts/EarthOrientationData/eop.html
>
> something obviously happened to dX and dY in 2019Q4 ?
>
> Does anybody here know if this is an artifact of measurements/models/calculations or if is this a real change in geophysics ?

I suspect it is showing that the current nutation model has a
deficiency in one of the terms with an 18.6 year period.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
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