[LEAPSECS] Straw men

Tom Van Baak tvb at LeapSecond.com
Wed Jan 11 12:45:57 EST 2012



> Another way of asking the question is 'what would the rate of leap seconds (or slope of TAI - UT or TT-UT)' if the

> definition of a second gave is an average LOD - 86400s of more like 1ms or 100us. And would we have had to have

> negative leap seconds...


Warner,

I'll track that down. I made plots once for a wide range of cesium calibration values.

Speaking of negative leap seconds -- if you look at any plot of LOD, such as this one on Steve's site
(http://ucolick.org/~sla/leapsecs/amsci.pdf) it's evident that earth has changed from slowing down to speeding up the
past few decades. Ironically the transition is right about 1972.

The longer-term plot (http://ucolick.org/~sla/leapsecs/lod.pdf) makes it clear there are no guarantees, but if this
trend were to continue we will have negative leap seconds 15 or 20 years from now. That would be good news for the
eliminate-leap-second-proposal since it would greatly extend the time that |DUT1| remains small and ignorable.

/tvb




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