[LEAPSECS] podcast from Orolia

[John Sauter]

On Thu, 2022-05-05 at 20:05 +0100, Tony Finch wrote:
> John Sauter via LEAPSECS <leapsecs at leapsecond.com> wrote:
> > 
> > One of the links on that page is to the draft of the resolutions
> > for
> > the 27th CGPM meeting, in November 2022. Resolution D notes that
> > "recent observations on the rotation rate of the Earth indicate the
> > possible need for the first negative leap second whose insertion
> > has
> > never been foreseen or tested". However, they are calling for an
> > increase in the maximum value of UT1-UTC by 2035, which would be
> > too
> > late to avoid the negative leap second, if current predictions hold
> > up.
> 
> I have just got today's Bulletin A. The LoD term in the equation for
> more
> distant estimates of UT1-UTC is now 24h - 280 µs, down from -270 µs
> last
> week. It has been dropping rapidly again since March, after
> increasing
> slowly for half a year..
> 
> My guesstimate for the negative leap second is now end of 2027, and
> likely
> to get closer if things continue like this!
> 

To illustrate Tony's point, here is a plot of the slope of the IERS's
estimates of UT2-UTC since 2005.  Values greater than zero predict a
negative leap second.  UT2 is UT1 with seasonal fluctuations removed.
    John Sauter (John_Sauter at systemeyescomputerstore.com)

-- 
get my PGP public key with gpg --locate-external-keys
John_Sauter at systemeyescomputerstore.com

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