When the New Year’s countdown begins in Berlin, people in Auckland are already sleeping off their hangover, but the bubbly has only just been put on ice in Hawaii. So how did it come about, our curious system of dividing the world into time zones?
Strange things happen to time when you travel. There’s that magical moment upon arrival in a far-off land when you reach for your watch and send the hands spinning past all the hours and minutes on the dial. It’s a small miracle: We’ve reached a different time zone and are obliged to physically change time. This gives us a strange sense of distance, of the size and dimensions of the earth, and also at that precise moment, an inkling of where we are: on a planet continually rotating in space, orbiting the sun.
How long was the flight? Nine hours? Twelve? Maybe it’s still bright daylight outside, or suddenly pitch-black? The moon may be out, or the sun up again. Night has flown by. What time is it exactly, here and now? And what does our internal clock say? A journey across time zones can be pretty discombobulating. We gain time, we lose time. We have to be awake when we want to sleep; we are expected to doze off even though we are wide awake. There’s also something exciting about traveling across 360 degrees of longitude – 180 in the East and 180 in the West. We could almost be on board the Starship Enterprise.
If we land in HKT, for instance, the time is suddenly UTC + 0800. Say again? Well, the clocks here tick according to Hong Kong time, which means eight hours have to be added to Coordinated Universal Time (UTC). Conversely, if we step off our plane in Tahiti, we have to deduct 10 hours from UTC. On the Chatham Islands in the South Pacific, it’s 12 hours and 45 minutes later than in London, and on the Line Islands, as much as 14 hours later. Confusing? You bet! But then, we all feel a little out of sync when the hours are flying around our ears. As familiar as we all are with the phenomenon of time change, not least through our personal experience of jet lag, the questions remain: Why do time zones exist? Where do they come from? Who invented them?
Strictly speaking, the sun is responsible for time zones because time was once measured solely by the sun. When sundials indicated the hour of the day, each place on earth had its own time. Noon was when the sun had reached its zenith on any given degree of longitude. High noon was precisely when the sunlight fell vertically, and the shadow the wandering sun cast was the hand of the clock. It was an ingenious idea, simple and reliable, except that the time was different in every place that was not on the same degree of longitude, even if those places were not very far apart. Cologne, for example, is near the seventh degree of longitude, Berlin near the 13th. Munich lies much farther west than Dresden – and everywhere, the sun reaches its highest point at a different time. So time – or to be more exact, true local time, varid from village to village. That’s why Cologne train station had signs up saying: “Difference in local time to Berlin, 25 minutes.”
The Internet and global trade are shrinking time and space today
For a long time, this sort of thing didn’t cause any problems. People moved slowly, traveling on foot, horseback or by horse-drawn carriage, so a few minutes made no difference. But that all changed with the advent of railroads in the mid-19th century. Based on local times in Berlin and Cologne, one and the same train would have left Berlin later than the time on the noticeboard in Cologne. And when the same train arrived in Cologne, the clocks would say a different time than clocks in Berlin. Complete chaos and minute-by-minute conversions would have been the consequence nationwide. And so a standard timetable with coordinated departure and arrival times was needed, hence the establishment of national standard times based on the time in the capital cities. Soon, Berlin time applied throughout Prussia, Munich time, throughout Bavaria. In the United States, where locomotives had to travel from New York to California, developments were quicker. By 1883, North America was already divided into four time zones, which would later become five.
Thinking in time zones as opposed to using sundials not only made life simpler and easier to coordinate and plan; it was also necessary because the world was moving faster and faster as technology came into its own. Telegraphy also called for synchronized clocks, initially in America but very soon worldwide. Representatives of 25 nations convened at the 1884 International Meridian Conference in Washington and ultimately established the Greenwich Meridian as the Prime Meridian – zero degrees of longitude running through the London district of Greenwich. The world’s present 24 time zones irradiate from it around the globe in 15-degree steps, westward and eastward – until they meet at the International Date Line (IDL) in the Pacific Ocean. All people had done was distribute time on the planet more roughly into a clear map of hours. That way, it was now far easier to coordinate when what happens where.
The true course of time, however, continues to run in cosmic dimensions with little regard for our human way of thinking. And where better to experience this than on a plane? Whether we fly west, following the sun, or east, from the setting sun into the night, we really do fly through days and nights, with no regard for the petty passing of minutes. In a small way, we return to an aboriginal state in which we measured time naturally and thought in terms of sunrises and moons.
Today, the experts are already forging new plans. Whereas at the end of the 19th century, it was the railroads that spelled the end of local, solar time, the Internet, global trade and international data communications are constantly shrinking time and space today. And also destroying them. That’s why Steve Hanke and Dick Henry, economics professors at Johns Hopkins University, claim that what we now need is a single world time completely divorced from the sun. That would mean that if it were 7 am in New York, for instance, the clocks in Frankfurt, Tokyo and Honolulu would also say seven in the morning. Across the Pacific, the Atlantic and the Arctic, everywhere the clocks would say the same time. Crazy? Yes and no – and ultimately just a further simplification of our concept of time.
The advantage: No one would have to think in strange time zones anymore, or change the time on their watch ever again. There would be one single standard time for global data traffic, for commerce, for everything.
The downside would be that most people on the planet would have to forget their cultural habits and get used to a new interpretation of time. While the people of New York (and everyone else on the same degree of longitude) could continue to rise with the new day and eat breakfast at seven, others would be taking their lunch break at seven, and in other places, going to bed at seven. The time would no longer say anything about everyday situations – in the end, it would have no relation to the position of the sun, to day and night. Would that be effective? Possibly.
But would it be good? Picture this: At midnight on New Year’s, the world’s entire population would be popping the corks – but in many places, the sun would still be high in the sky. Nighttime firework displays would no longer light up the skies in those places, and many people would be raising a glass to the New Year the moment they got up: sipping bubbly instead of brushing their teeth. The sun cares little about any of this, and as an old Indian saying goes: “People say time passes. Time says that people pass.”
Local Apparent Time is based solely on the actual position of the sun overhead.
Greenwich Mean Time is based on the Prime Meridian, which passes through the London district of Greenwich.
Coordinated Universal Time was introduced in 1972. It takes the Prime Meridian as its reference point, just like GMT.
Central European Time is the official time standard for Central Europe and parts of Africa.
Marc Bielefeld likes flying through time, particularly eastward into the night with the sun setting at his back rising in front of him. He wrote our story about the history of time zones.