[LEAPSECS] Leap smear

[Ian Batten]

> 

> Let's see…1 ppm is 0.0864 seconds per day.  That is a leap second (or equivalent drift) every 11.57 days.  A leap hour (presuming such is implementable) every 114 years.  Is this acceptable?  Says who?  What process should be followed? 


Exactly the same process that the UK followed on the 27th of October 1968.   You wouldn't be leaping UTC, you'd be leaping civil time.  We're used to that.    You just spring forward, but don't fall back.  Need the leap hour in the opposite direction?  Don't spring forward, but leap back, as we did on 31st October 1971.  What's so difficult about it?

Changing timezones by an hour has happened with monotonous regularity: Portugal's done it several times, for example.  Britain's tried UTC+0/UTC+1 (most commonly), UTC+1 (British Standard Time, 1968--71), UTC+1/UTC+2 ("British Double Summer Time", 1940--1945), and UTC+0/UTC+2 (1947), so four civil time standards in the lifespan of people still alive.

There are many arguments why the proposal to move the UK (or at least not-Scotland's) time to align with mainland Europe is a good one, and some why it's a bad one, but no-one sane has attempted the "oh, correcting our watches is really hard" because people will just laugh.

There's been multiple leap-hours in my lifetime, including one-off ones, are likely to be more, and within my parents' lifetime there's been leap-two-hours, twice.  Why is one extra leap-hour per century any different?

ian