The Problem with Permanent Daylight Saving Time

A populist movement has arisen in recent years to make daylight saving time (DST) permanent. A change supported by perhaps more than half of U.S. adults. But there are some major problems which people do not think all the way through. People only consider the benefit of an extra hour of daylight in the evenings during winter months. Satisfied with themselves, they move on with their lives, promptly shutdown their brain, and don’t consider the full scope of the issue.

First of all, what is DST? I think a lot of people have difficulty understanding this. All DST really does is mess with the number on the clock to trick people into waking up an hour earlier. That’s it! The reason why this trick works is because it is temporary—only used during the summer when daylight hours are longer.

My central thesis is that human activity is ultimately governed by the Sun and not by a number on a clock. The times chosen for the start of school, working hours, bus schedules, etc. have all been figured out over decades to best balance the needs of society with the human circadian rhythm as entrained by the Sun. When someone proposes permanent DST, what they are really proposing is for all of this history to be thrown out and to start over. You see, these times are not fixed. They can be changed to best meet the needs of society.

Under permanent DST, when people are waking up in the dead of winter well before the Sun, they will think to themselves: “What the hell am I doing? Why am I waking up so early!” Over time instead of viewing 9 am as a reasonable time to start work, people will start to think 10 am is better. Likewise, parents will pressure schools to start school later. Perhaps 9:30 instead of 8:30. Local municipalities will push back bus schedules, and so on. A change to permanent DST may work for a time. But over years, we will begin to see a break down—a nullification of the intended result. What then? Will we then propose to move the clocks forward another hour? Will the days march around the clock as we try to force people to wake up earlier?

How do I know people will reject permanent DST and try to nullify it? Because it was tried once before in the U.S. in the 1970s and failed. While initially supported by a large percentage of people, Americans strongly disliked waking up and going to work and school early in the cold dark winter months. Public opinion quickly shifted after the first winter when the change was enacted.

In the present era, nineteen states have passed legislation to observe DST all year. However, they are unable to make the change due to The Uniform Time Act of 1966. This federal law if changed could see a large number of states suddenly on DST permanently. It’s beginning to look like history could repeat itself.

If human activity is ultimately governed by the Sun, then I strongly prefer to have the clock aligned with the Sun. Historically, this was accomplished by setting clocks to local mean time where 12 o’clock was set to solar noon at a particular location as averaged throughout the year. Obviously, we have compromised a bit on this with time zones, but the intent is still there to keep the clock as closely aligned as possible. Year-around DST, however, is a permanent offset thereby forever skewing the clock relative to the Sun. Not a very desirable outcome.

Finally, sleep scientists overwhelmingly oppose permanent DST and instead advocate for permanent standard time as best for human health. This isn’t a coincidence. People have already figured out the optimal times for human activities to start based on human circadian rhythm as entrained by the Sun to maximize societal benefit.

If you want all of society to wake up earlier, negotiate. Make a case to the societal benefits. Convince people to move start times earlier. But, don’t mess with the clock.

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