Playing with Time
Changing the clocks twice a year has become a minor tradition in many countries. Like the first buds after winter or the first falling leaves, the start and end of Daylight Saving Time (DST) is a reminder of seasonal change. This ritual used to be more elaborate as we were forced to manually change every clock we owned, but it is now mostly automatic as clocks have gotten more sophisticated. The one thing that hasn’t changed is the grousing as an entire country is dragged into an adjacent time zone during the middle of the night leaving its inhabitants with a mild case of jet lag. And as parents, pet owners, or farmers will tell you, it is no small effort trying to get children and animals to change their usual feeding and sleeping schedules. For early risers, DST feels more like Daylight Stealing Time — an injustice created by people who like to stay up late. One would hope there is some benefit to all this inconvenience.
Prior to the industrial revolution, there was little need to keep precise time in daily life. Once society became tied to regular timekeeping, the natural flexibility of our relationship to the sun was interrupted and the idea of seasonal clock adjustment likely occurred to many people. Notable early proponents on record include the New Zealand naturalist George Hudson in 1895 and English builder William Willet in 1907. Clock shifting in the U.S. was officially tried during WWI and WWII, but was so unpopular, it wasn’t until the 1966 Uniform Time Act that it was permanently adopted.
What Are We Saving?
An original intent of DST was to save energy, but the energy benefits have come into question. Energy studies have been aided by the many changes to DST policy over the past two decades worldwide which create natural experiments where researchers can compare actual effects of DST implementation.
For example, an energy analysis was completed for the state of Indiana which fully transitioned to DST in 2006 as a result of the Energy Policy Act of 2005. The study was significant because it was one of the first based on actual energy data rather than estimations. The analysis found that DST reduced lighting costs but increased heating and cooling costs such that total energy consumption actually increased a few percent. Since the transition from energy-hungry incandescent lighting to efficient LED lighting was just beginning in 2006, the energy savings of DST are likely even worse today.
Other recent studies from across the globe (e.g., Argentina, Mexico, Spain, Slovakia, and Turkey) have come to roughly the same conclusion that clock shifting has negligible impacts on energy use (usually 1% or less). This is not surprising considering that DST doesn’t create daylight. Energy saved at one end of the day is often spent at the other.
A better reason for DST might be public safety since, in theory, more evening daylight might prevent traffic accidents. However, a 2020 paper that analyzed 732,835 fatal motor vehicle accidents in the U.S. between 1996 and 2017 found a 6% increase in the fatality rate for the week after the spring transition but no change during the fall transition. This suggests that additional lighting doesn’t noticeably lower risk, but sleep deprivation increases risk. Likewise, another 2020 paper found that, for the years 1970–2018 in Vienna, Austria, daily mortality rates increased by 3% in the week of the spring transition.
As the science of circadian biology has matured, the consensus is that DST is not worth the purported benefits. A 2019 position paper endorsed by the Society for Research on Biological Rhythms calls for an end to DST noting that humans reap multiple health benefits when their body clock, set by sunlight, aligns with their social clock, set by their official time zone.
So, why do we still have DST? According to Michael Downing, author of Spring Forward: The Annual Madness of Daylight Saving Time, business lobbyists are the real reason we have DST. Businesses that cater to leisure activities believe that another hour of light on summer evenings will encourage consumers to spend more time consuming their products — sports equipment, ice cream, etc. Businesses are also partially responsible for recent extensions of DST. Candy manufactures lobbied for years to include Halloween in DST arguing that an added hour of light would increase child pedestrian safety (as well as the number of trick-or-treaters and candy sales).
So, despite good intentions, DST is really a business stimulus plan disguised as an energy savings and public safety measure that doesn’t actually save energy or lives. If this strikes some as quintessentially American, the early inspiration for DST is all the more fitting.
In a 1784 letter to the Journal of Paris, an elderly Benjamin Franklin joked that, because he rarely rose before noon, he was shocked to find the sun up at 6 AM when his maid forgot to close his window shutters the previous evening. Mr. Franklin made satirical suggestions for taking advantage of this free unused sunlight including rationing candles, taxing window shutters, and firing cannons at sunrise to wake the lazy. At the heart of Mr. Franklin’s joke was his now famous but still rarely followed advice that, “early to bed and early to rise makes a man healthy, wealthy, and wise.”
Is the End of Daylight Saving Time Near?
Let us first acknowledge that DST has always been useful for only a narrow slice of the world. It is rather pointless in countries near the equator where there is a nearly consistent 12 hours of daylight throughout the year. It is also less useful as one approaches the poles. Reykjavík, Iceland receives 4.5 hours of sunlight at winter solstice and over 21 hours at summer solstice. Shifting the clocks only one hour to deal with such extremes is unnoticeable. Predictably, after trying it for 30 years, Iceland abandoned DST in 1968. Russia, another polar country, permanently ended DST in 2014 after trying year-round DST for several years.
DST will also become less useful in a modern world that is becoming more uncoupled to the clock every year. Farmers have always ignored the clock and factories try to ignore daylight, but an increasing number of jobs now have flexible hours. Likewise, remote work has reduced the need to follow mass transit timetables. Even our leisure is becoming time-independent. How often do people watch live programming anymore that requires being at home in front of a TV at a specific time? We now access content when and where we want. As our work and play increasingly happens when it is personally convenient or at least independent of sunlight, we move away from the traditional 9-to-5 clock-based industrial society for which Daylight Saving Time was intended.
Cultures tend to hold onto habits long after they are no longer valuable, but most of the world has abandoned DST at this point. North America and Europe are the notable holdouts. The European Union voted to end DST in 2018, but the end originally scheduled for 2021 was delayed due to the pandemic and arguing over what time to settle on. However, once the EU gives up DST, it may only be a matter of time before the U.S. is alone — much like our inexplicable refusal to fully adopt the metric system. So, it’s anyone’s guess as to when DST will finally disappear, but its time may be near.
UPDATE — After stalling in committee for years, the U.S. Senate passed the Sunshine Protection Act by unanimous voice vote on the Ides of March, 2022. This attempt to move the U.S. to permanent DST is a bit more controversial with the rest of the country, especially medical researchers. While the impact would be less noticeable in southern states where daylight is more evenly distributed throughout the year, northern states would have to deal with even darker winter mornings. Getting out of bed in January would require even more fortitude. A Washington Post article nicely illustrates the later sunrise.
Is there anything a person who prefers standard time can do? Yes, move to the eastern edge of a time zone. For example, Eastern Standard Time is based on the meridian of 75° W longitude which passes almost directly through Philadelphia, PA. Thus, solar noon (when the sun is at its highest point in the sky) and civil noon (when the clock reads 12 PM) are the same during standard time. Residents of Boston are about 15 minutes ahead of Philly and the West Quoddy Head lighthouse in Maine experiences solar noon as early as 11:26 AM. Shifting to DST year-round makes solar noon occur an hour later, so the east Mainers would still only have a half hour discrepancy between their solar and civil noon. Not too bad.
Meanwhile, more western cities, such as Buffalo and Cleveland, have a lagging solar noon by 15 and 30 minutes, respectively. Ontonagon County, in Michigan’s Upper Peninsula, is at the westernmost section of the Eastern Time Zone and has a solar noon at about 12:58 PM. Permanent DST moves solar noon to almost 2 PM. This is great if you love late summer sun, but tough on snowy winter mornings and not so great for your health.
The benefits of moving east applies to all time zones, but the amount of time gained varies by the shape of the time zone (a whole other interesting topic).
If moving seems too bold, consider that over the years we have continually played around with clock time seeking resolution to problems that the clock didn’t cause. If history has any lesson, it’s that if you wait long enough, the clocks will change again.
