Re: [Tzdist] example json snips for systems that count leap seconds

Paul Eggert <eggert@cs.ucla.edu> Tue, 13 January 2015 21:43 UTC

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Date: Tue, 13 Jan 2015 13:43:00 -0800
From: Paul Eggert <eggert@cs.ucla.edu>
Organization: UCLA Computer Science Department
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To: Martin Burnicki <martin.burnicki@burnicki.net>, Steve Allen <sla@ucolick.org>, Time Zone Data Distribution Service <tzdist@ietf.org>
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Subject: Re: [Tzdist] example json snips for systems that count leap seconds
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On 01/13/2015 11:43 AM, Martin Burnicki wrote:
> From my own experience I'd say an application programmer who is just 
> interested in an enumeration of leaps second events would expect to 
> see dates like
>
>   2015-07-01T00:00:00Z
>
> instead of
>
>   2015-07-01T00:00:36Z
>
> for the leap second events. However, if it's made clear that the times 
> are TAI, not UTC (is 'Z' correct, then?)

I don't think it's correct.  TAI is not connected to the rotation of the 
earth, so it's misleading to say that TAI has days or dates. The IERS 
uses UTC or JD for dates and times of leap seconds, and we should do the 
same.  UTC is better than JD, as UTC is better-known among non-astronomers.