[LEAPSECS] What's the point?

[Tony Finch]

On Mon, 14 Feb 2011, Mark Calabretta wrote:

> On Fri 2011/02/11 15:42:41 -0000, Tony Finch wrote

> >

> >See for example

> >http://six.pairlist.net/pipermail/leapsecs/2011-January/002124.html

> >where Rob Seaman wrote "Civil timekeeping is cumulative. Tiny mistakes

> >posing the problem will result in large and growing permanent errors."

>

> You'd have to be a lawyer to be able to interpret that as an argument

> for the "quadratic catastrophe" supporting UTC.


Yes, it isn't a very good quote, just the first one I found with a bit of
searching.

Rob frequently argues that we can't use a pure atomic timescale as the
basis of civil time because of the quadratically increasing offset between
UT1 and TAI. You yourself made the same argument in your previous message.

The counter-argument is mainly to point out that the offset is negligible
from the point of view of the majority of people. It won't become
uncomfortable until about a thousand years in the future, by which time
leap seconds will be stretched to breaking point. Furthermore using
timezones to keep civil time in sync with the sun leads to simpler
software and it will work for over ten thousand years.

So it is not correct to argue that because abolishing leap seconds will
lead to a quadratic catastrophe therefore we must keep leap seconds. It's
wrong mainly because the catastrophe isn't actually a catastrophe. There
is a problem for people who need UT1, because they will need to upgrade
their systems that deal with it. But the magnitude and accelerating
increase of DUT1 are quite managable.

Tony.
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