Every time we go on or off Daylight Saving Time, like clockwork (forgive the pun), there is a flurry of articles defending or attacking Daylight Saving Time (‘DST’). Well, put me in the supporters of Daylight Saving Time camp–I HATE going off it. Living in Boston, I don’t actually know very many (any, really) people who like ‘leaping back.’ Why?

Well, it’s the longitude, baby. And it’s something I think any study of the effects of leaving or entering DST has to take into account. Let me explain.

Consider three cities on Eastern Standard Time, Boston (latitude/longitude 42˚ 20.1′ N, 71˚ 01.0′ W), Erie, PA (42˚ 07.5′ N, 80˚ 05.2′ W), and Ann Arbor, MI (42˚ 16.5′ N, 83˚ 43.8′ W). They all have almost the same latitude, but move east to west across the time zone.

Now, let’s look at the sunrise/sunset times for each city for the Monday after Thanksgiving (Nov. 28):

Erie, PA: 7:25am/4:51pm
Ann Arbor, MI: 7:40am/5:05pm

In fairness, I can understand why people in those cities want to fall back–if we didn’t, it would be around 8 – 8:30am before it was significantly light outside. And the sunset means it really doesn’t start to get dark until around 6pm.

And Boston? Well: 6:49am/4:14pm

Ugh. You get woken up earlier on weekends (um, yay?), and meanwhile it’s pitch black at 5pm. Like I mentioned, I’ve met very few Bostonians who like falling back. Businesses don’t like it either. Given that we fix our schedules to concrete times, I think any estimate of the effects of jumping ahead or falling back must include longitude* effects.

Also, I fucking hate leaping back. Make Daylight Saving Time standard.

*This is different than longitudnal effects.