[LEAPSECS] Leap smear

[Ian Batten]

> 

> So let's say consensus is reached on 1 ppm, or maybe 10 ppm or 0.1 ppm.  What is this tolerance measured against?  Right!  Time-of-day = mean solar time.  What is "LOD" in all those plots?  Requirements describe the problem space.  Mean solar time is a requirement.  1 ppm would be a specification against a proposed solution suitable for evaluation by a trade-off, risks, costs, schedule, sensitivity analyses, etc.


So why aren't all those exotic investigations necessary when countries change timezones, which happens with monotonous regularity?    In this case, no-one is proposing to change the SI second, rather just to use it as monotonic counter.    We've already established that the link between civil time and solar time has an uncertainty measured in multiple minutes, and we've already established that one-hour steps in civil time are trivial to implement, because they happen twice a year.  All we're left with is a vague need to keep the sun roughly overhead at noon (although there are few riots in Brest, France, which in the summer is about 2hr10 unhitched from solar time) which we can manage with daylight saving time type adjustments.     The rest is just "sky is falling" stuff,.

ian