[LEAPSECS] UTC Redefinition Advanced

[Jonathan E. Hardis]

On Nov 2, 2010, at 11:05 AM, Rob Seaman wrote:


> On Nov 2, 2010, at 7:06 AM, Clive D.W. Feather wrote:

>

>> The reason I haven't been involved in this thread up to now is that  

>> I spent the last week in a place where apparent solar time and  

>> official clock time were about 7800 seconds apart. It was quite  

>> curious being near the tropics and yet at 08:30 the sky was still  

>> dark.

>

> ...

>

> Eliminating leap seconds would introduce a permanent secular trend  

> (no matter how small).


So the 30 messages in my in-box  this evening arose from a belated  
reply to I message I posted a week ago.  Oh, well.

Rob ... you're absolutely right.  Eliminating leap seconds WOULD  
introduce a secular trend ... IF (and here's the part I haven't  
convinced you about yet) no other means for compensating for it is  
implemented, FOREVER AND EVER.

This is not what the ITU is discussing.  They are not making policy  
FOREVER AND EVER.  They are dealing with a much more limited  
question:  are occasional, sporadic, and unpredictable leap seconds,  
that much of our infrastructure has difficulty dealing with, an  
appropriate means of dealing with the secular trend TODAY?

Society -- and computers -- don't seem to have much problem with leap  
years, which occur on a preset schedule every 97 years out of 400.   
Why shouldn't leap seconds be constructed the same way?  If the ITU  
makes the decision to allow DUT1 to exceed 0.9 second, then some  
decades from now the ITU could reintroduce leap seconds -- with years  
of advance notice -- on a regular once- or twice-a-year schedule.  In  
the meantime, as long as DUT1 remains under a couple of hundred (which  
would take centuries to happen), the public is apt to be less  
inconvenienced than they are with the present system.

      - Jonathan