[LEAPSECS] Cost: getting rid of GMT & discontinuing leap seconds

[ashtongj]

Here is a cost that has not yet been mentioned. Many sources still refer 
to the basis of civil time (before adjustment for time zone and daylight 
saving) as Greenwich Mean Time. This can still be justified because 
although the meridian for which UTC is the mean solar time moves over 
the surface of the earth, and does not consistently pass through the 
crosshairs of the Airy transit, it most likely remains on the Royal 
Observatory, Greenwich. (I estimate 0.9 s of time corresponds to about 
260 m at that latitude.) Even if the meridian does not stay on the 
grounds, it at least stays within the London Borough of Greenwich. But 
once leap seconds are abandoned and |UT1 - UTC| becomes large enough to 
move the meridian entirely outside Greenwich, it will be necessary to 
modify all textbooks, monuments, and museum exhibits containing 
explanations of civil time accordingly. It will also be necessary to 
modify all computer programs which keep civil time to replace GMT with 
the appropriate symbol (I have supposed the symbol UTC will continue, 
but who knows).

Some may think that the preceding paragraph is light-hearted, and maybe 
it is. I do think, however, that the time keeping authorities in 
English-speaking countries have proven incapable of getting the public 
to stop using the symbol GMT. Indeed, NIST and USNO have so little 
influence on the rest of the government that they can't even get the US 
government to stop using the symbol GMT. The inability to enforce 
whatever decision is finally agreed to is a concern.

Gerry Ashton