Time zones are dumb

Matt Bernhard
9 min readMar 19, 2017

About a year ago, I was catching a 10 o’clock flight from Houston to Detroit. I arrived at the airport at about 9 A.M. and went to the counter to check my bag. I scanned my boarding pass, and then the person working the Southwest desk look at me like I was crazy. She said, “I don’t think your bag is going to make this flight.” This was puzzling to me, as Southwest’s baggage policy requires you to check a bag no later than 40 minutes before your flight (which I had previously discovered the hard way). I had plenty of time. What was wrong?

“Actually, I don’t think you are going to make your flight either. It just left.” What? Glancing at my boarding pass, I see plainly printed, “Departure time: 9:00 A.M. local time.” Crap. I’m normally fairly fastidious about travel. How did I mix this up? Fortunately, they rebooked me on the next flight out free of charge, and I eventually made it to Detroit (Southwest FTW). But still, I was confused. How did I miss this flight?

As I trundled my way through security and to the gate, it dawned on me: I had been relying on a calendar app for my flight time. My calendar is set to eastern time. My flight was in central time, and entered into my calendar automatically from the confirmation email the airline sent me. Apparently this feature doubly accounted for the time change, so my 9 A.M. flight was put onto my calendar as a 10 o’clock flight eastern time, and my calendar switch from eastern to central without adjusting the flight time. The net result was that my calendar had my flight at 10 A.M. central time.

The moral of the story is to always check your boarding pass for your flight time. But it got me thinking more critically about time zones, travel, and computers, and I’ve come to a conclusion. Time zones are dumb. They are a vestigial holdover from history, and we should get rid of them.

A Brief History of Time (Zones)

There is a long history of time and time keeping, far more than I want to go into (or that I know). I will give a rough summary for context, but note that I’m omitting a lot, including sources, for brevity. Feel free to verify this info on your own (and call me out if I’m wrong).

Time has been an essential part of human civilization since the first people began to worship the sun. Without some notion of time keeping, planning day-to-day activities would be very difficult. It isn’t as if our ancestors just wandered around each day, doing business simply through chance encounters. No, they relied on the sun, and they had relatively precise tools mark time leveraging the sun: sundials.

In the event that you don’t know, the sun doesn’t shine on every part of the Earth equally. The day and night cycle is a feature of the Earth’s rotation, and as a result, it is day in Asia while it is night in the Americas. When a sundial says it’s noon in one part of the world, it would read something completely different at that instant somewhere else. Even a distance of a few hundred miles can account for minutes of difference.

For the majority of human history, this was never really a problem. The fastest we could travel was a few tens of miles an hour (by boat), and we didn’t have speed-of-light communication, so using sundials as a standard measure of time wherever you were was a pretty good way of doing things. In fact, even after accurate mechanical clocks were invented, they were still pegged to solar noon wherever clock was (solar noon is when the sun is directly overhead, hence high noon in a lot of western movies).

The Industrial Revolution, well, revolutionized this. Suddenly we could travel fast enough to distort the time measured by the sun as it tracked across the sky. This was a huge problem for trains: knowing when a train that left somewhere else hours ago would arrive is necessary so you can have a clear track and optimize routing, track switches, etc. And you thought those high school algebra problems about two trains leaving St. Louis were hard!

Source: https://commons.wikimedia.org/wiki/File:Bittern_locomotive_king's_cross.JPG

Train travel led to the establishment of Railway Time, which binned smaller differences of a few minutes in distant cities together, so that a train from London to Bristol would arrive at the same time in both places, even though their respective solar noons were different. Some variant of Railway Time was eventually adopted in most places in a sort of ad hoc way, morphing into Greenwich Mean Time (GMT). Offsets to GMT were used in many places around the world (thanks colonialism!), and it became the de facto standard.

In the late 1950s and early 1960s, computer technology and space travel had come about, and a more rigorous standard of time was needed both for fine-grained precision and consistency across even greater distances than just trans-continental. As the human understanding of the physical world had also come a long way since the days of Railway Time, time and time zones were just two of many quantities that were standardized around this period. This new standard was Coordinated Universal Time (Temps universel coordonné, UTC), and is used in some capacity by every country in the world, seeing its last adoption in 1986 by Nepal. However, one country has since left UTC, but it seems unlikely that others would follow any time soon. Practically, UTC and GMT are equivalent in most cases.

In summary, we have time zones because there was once a time when people could travel about as fast as they could communicate. Time had to be standardized and agreed upon prior to travel, and the only good way to establish what time it was in your time zone was to use the sun, or to use the sun in another time zone and offset. None of this is true any more. We have near-instantaneous communication, and we have already established protocols to establish time automatically on networked computers (admittedly not without flaws, but these can be addressed in the effort to abandon time zones, since it will be non-trivial anyway).

We don’t need time zones. Of course, that’s no reason to get rid of them. Time zones make life unnecessarily difficult, and likely cause a significant amount of economic inefficiency. Those are good reasons to get rid of them.

Time zones suck for people

While my own personally folly has caused me to greatly disfavor time zones, I don’t think I am an outlier. Time changes are bad in general. People have to adjust, which leads to lack of sleep, irregular eating cycles, and general misery. It’s easy to make mistakes about what is happening when. For reference, Daylight Saving Time (another terrible time institution in practice around the world), may cost hundreds of millions of dollars in lost productivity in the United States alone. In fact, this impact is so bad that some U.S. states have already abandoned the practice, and many more have pending legislation to follow suit (though, much to my chagrin, they don’t always follow through).

To be sure, not all of these inefficiencies apply to time zones. You would still eat dinner at 7 P.M. in New York but 10 P.M. in San Francisco (assuming we pick eastern time as the global standard, which will be a contentious debate), and traveling between the two would cause some jarring. But we would eliminate scheduling problems with teleconferencing and we could prevent cases of confusion like my missed flight.

Time zones suck for computers

I wasn’t the only one to blame for missing my flight, though. Implementing time in computers is a remarkably difficult thing to do. Since they can’t exactly look at the sun to calibrate their clocks, computers rely on some external source to keep track of time. Often times this is a special battery powered component that relies on the oscillation of crystals (like quartz) when a current is passed through them. Without these kinds of independent time sources, computers often try to keep track of time internally, counting “clock ticks” since an established point in the past (midnight UTC, 1 January 1970, the beginning of the UNIX epoch). However, if the system ever loses track, it has to deal with “clock drift”, akin to the problem faced by mechanical clocks, which are ever so slightly imprecise that over time they lost synchronization with real time. This then also incurs the issue of synchronization, as we saw with clocks on the early railways, as different computers have different clock drift, and getting them to agree on a time is hard (though as previously mentioned we do have some idea of how to do it).

Disregarding the difficulty of a computerized notion of time, time zones provide another hurdle that makes everything more complicated than it should be. Just ask Tom Scott. Without time zones, there would never be the potential for ill-defined behavior. Apps wouldn’t have to worry about compensating for time zones of the user or of other apps. Stuff would just work.

Time zones aren’t future proof

It’s telling to look at how time zones will fare in the future. As technology has advanced, humans have gained the ability to travel to more extreme places, and often times this does not mesh well with time zones. For instance, the twentieth century saw the first human expeditions to the poles of the Earth. Theoretically, all timezones converge at the poles, and depending on your radius from the poles you could literally walk around the clock. But in practice, time of day doesn’t mean much near the poles. The sun is up, or it isn’t, and this largely depends on the season. Time zones don’t work at extreme latitudes.

The twentieth century also saw human space travel for the first time. This is where time zones really lose their usefulness. Just orbiting the Earth means that you can see the sun rise and set many times an hour, so there is no notion of a traditional day and night, much less a geographically-dependent solar noon. Space programs peg their time to GMT/UTC, since this enables space flights to coordinate with their mission control centers back on Earth. This is a hack that is approximately the same as abolishing time zones, but as of yet it only applies to space travel.

We are also rapidly approaching human colonization of other planets, where again time zones as they currently function make no sense at all. A day on Mars is 40 minutes longer than on Earth, so diurnal clocks on each planet would rapidly get out of sync for long phases even without having to account for time zones on the Earth. If we eventually reach further into space, the sun will have even less bearing on the environment, meaning that any notion of time defined strictly by solar synchronization would quickly fall by the way side.

Greater distances in space also lend themselves to the effects of relativity and the fundamental limitation of the speed of light. Synchronizing clocks would be somewhat challenging, but certainly possible. This would only be complicated by compensating for Earth time zones, providing another reason for abandoning time zones.

In short, the future of humanity is beyond Earth. Time zones don’t work beyond earth. Abolishing time zones isn’t just something that might or should happen. It’s inevitable.

Image sources: https://en.wikipedia.org/wiki/File:Analogue_clock_face.svg, https://en.wikipedia.org/wiki/File:The_Earth_seen_from_Apollo_17.jpg

Standard Earth Time

If we are to abolish time zones, of course we need a viable replacement. The obvious solution would be to use UTC everywhere, even in space. Humans naturally have an approximately 24-hour circadian rhythm (sleep-wake cycle), and we evolved with our sense of time bespoke for the Earth. Using an Earth day as the standard for time everywhere in the human-universe just makes sense, and we can hasten our transition into a space-faring civilization by adopting a standard, global 24-hour clock now.

Time zones are dumb. We don’t need them anymore, and we will eventually get rid of them anyway. Were I king of the world for a day, I would abolish them.

(While I’m at it, I might even fix time’s screwy base 60 units. Of course, the last time someone tried that a lot of people lost their heads)