Wednesday, March 31, 2004

So what is UTC and why am I using it?

Yes, it's true, I don't live in Greenwich, England. No, the local time is not 02:15 as I write this. So why am I using UTC? UTC stands for Coordinated Universal Time. This is the internationally agreed upon reference time for the entire planet. It is equivalent to the local time in Greenwich, England, without any daylight savings monkey business added or subtracted. The time is kept by several Atomic clocks around the world, kept in sync with one another. Atomic clocks are extremely accurate. Alas, the planet Earth is not so accurate. So the atomic clocks have to be adjusted every so often so the UTC doesn't vary from the actual astronomical time determined by the planet by more than a very, very small amount (sorry, I forget just what that small amount is and I'm too lazy to look it up right now).

I made a conscious decision to use UTC. Although I want this blog to be about personal (and thus somewhat local) experience, I also want a global frame of reference. It's the "think globally" part of that old environmental saw.

Yes, it's rather abstract, and thus not very concrete and experiential, but all official timeframes are arbitrary and abstract. If I wanted to be absolutely concrete, I would have to resort to describing time of day in terms of things I can directly, locally observe, such as sunset, sunrise, local noon, etc. So I guess I want to bridge the abstract and the concrete.

This will explain why posts dated April 1 are already appearing to you even if where you live it is still March 31. Someplace in the world (namely five hours ahead of me), it is April 1.

Thus is my ramblng exposition on UTC. (By the way, "UTC" was a compromise between English "CUT" and French "TUC.")

This is the exact UTC right now. (By the way, Daylight Savings Time starts this weekend if you're in the U.S.)

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