Why do we do change our clocks twice a year for Daylight Saving Time? The answer involves Benjamin Franklin’s trusty almanac, bug hunting, and coal-powered warfare (notice that farmers are not on the list).
“Spring forward, fall back.” Every second Sunday in March, groans echo throughout 75 countries in the world as everyone gets up an hour earlier than their body is used to. And every first Sunday in November, those same people rejoice when they get to sleep in for an extra hour. The idea is to maximize sunlight during waking hours in the Northern Hemisphere’s spring and summer by shifting our clocks to add an hour of sunlight to the end of the day. We’re not actually losing or gaining any time; we’re simply robbing an hour from March and giving it to November to “save” daylight. But who is the Robin Hood responsible for such theft?
The Origin of Daylight Saving Time
You’ve probably heard that Daylight Saving Time (DST) was proposed to benefit farmers who wanted extra daylight to work in their fields later in the evening, but this is a myth.
In 1784, Benjamin Franklin published a satirical letter in the Journal de Paris, lamenting that most Parisians slept until noon (at least, he did) even when the sun rose at 6:00 a.m. According to his almanac, which listed the hour of the sunrise and sunset each day, they were missing out on six whole hours of natural sunlight but burning candles late into the night. Though Franklin didn’t suggest a shift in clocks, he suggested a shift in schedules to align life more fully with the rise and set of the sun, who “gives light as soon as he rises.” He calculated that, by doing so, the country could save the modern equivalent of $200 million by “the economy of using sunshine instead of candles.”
As Franklin’s letter hints, the primary policy rationale behind DST is actually energy conservation, though society was burning coal more than candles by the time it was proposed.
In 1855, a New Zealand entomologist named George Hudson suggested a two-hour time shift to allow for more light in the evening hours to go bug-hunting. In the early 1900s, William Willett independently came up with the idea to help Great Britain avoid wasting daylight and proposed it in Parliament, backed by Winston Churchill and Sir Arthur Conan Doyle—but to no avail.
Finally, in 1916—two years into World War I—Germany took notice of Willett’s idea of moving the clock forward and adopted it as a way to conserve energy during the war effort. Almost every other country involved in the war soon passed daylight saving laws. Because industrialized nations were primarily using coal power, the time shift actually did save energy and contribute to the war effort during this era.
(And in World War I, coal was power. As Germany faced international blockades and domestic shortages of necessary resources, the British allied forces’ control of the coal industry became one of the decisive, war-ending assets that led to the defeat of the Axis powers. Coal fueled the British blockade that weakened Germany to the point of defeat.)
Though DST was mainly a way to save fuel, another economic objective behind it after the war was to encourage people to use the extended daylight hours in the evening to shop, attend sporting and recreational events, and spend more time outdoors.
Daylight Saving Time in America
The United States formally adopted Daylight Saving Time in 1918. The dates when the time change occurs have been changed over the years, and the most current legislation is the 1966 Uniform Time Act, which regulates time zones and the observance of DST across the country.
Currently, all states but Hawaii and Arizona currently observe Daylight Saving Time. Hawaii abandoned Daylight Saving Time in 1967 because it is close enough to the equator that the sun generally rises and sets around the same time each day, regardless of the time of year. (Likewise, most tropical nations and territories do not observe Daylight Saving Time either because variations in day length are negligible.) Since 1968, Arizona has permanently been on Mountain Standard Time, with the exception of the Navajo Nation and the Hopi Reservation, which do observe Daylight Saving Time. (This means that if you drive east on the Arizona State Route 264 while DST is in place, you will change time zones six times in less than 100 miles!) Due to its location, there is plenty of daylight in Arizona year-round, and residents benefit from cooler temperatures in the evening rather than more sunlight.
In 2021 alone, thirty-three states have introduced legislation addressing the issue of DST. In the last four years, nineteen states have passed legislation or resolutions to enact DST year-round. However, they still need the approval of Congress for this legislation to take effect. Some critics of DST argue that permanently turning our clocks ahead an hour will not only eliminate the nuisance of the time change but, more importantly, alleviate some of the health consequences of DST in the spring while maintaining quality of life in the winter. Different states vary in their preference of remaining permanently on daylight time or standard time, but, as noted by the National Conference of State Legislatures, “the actual March and November time changes are almost universally reviled because of all the accompanying adjustments we must make, like coming home from work in the dark and the slower-than-expected resetting of our internal time clocks” (NCSL, 2021).
The Pros and Cons
We know we can’t create more daylight, even if we tried. The earth will continue its rotation and revolution, unhindered by our puny human efforts. But we can manipulate the way we think about it by altering our construction of time. One benefit of DST is that it provides longer evenings in the spring and summer since we wake up an hour earlier. The extra hour of light provides time for outdoor activities, encouraging a more active lifestyle and increased spending in the tourism and recreation industries.
A potential benefit of DST is increased safety. Some studies have found that DST contributes to a reduction in pedestrian fatalities and crimes such as robbery in the evening hours simply because it stays light later. However, other studies have found that fatal car crashes increase by 6% in the week after we “spring forward,” especially in the morning hours, due to a disruption in sleep cycles. Sleep deprivation causes more drowsy driving incidents during this period, as well as contributing to an uptick in heart attacks, strokes, and workplace injuries. These unwarranted interruptions in our circadian rhythms seem to do more harm than good. One researcher commented, “It would be better for sleep, the body clock, and overall health to have more morning light and less evening light, as is the case under permanent standard time” (Ries, 2020). However, it’s important to note that these disruptions are temporary, often lasting just a few days. For example, the incidence of heart attacks rises 25% on the Monday following the March change to DST, but the overall incidence of heart attacks throughout that week is average as compared to the rest of the year.
The most often cited benefit of DST is that our daily routines coincide more with the hours of natural daylight, reducing the need for artificial light and yielding energy savings, albeit very modest ones—a meta-analysis found average energy savings of 0.34% due to DST. Energy savings are largest farther from the equator, while subtropical areas actually increase energy use due to DST. Another study found that even when electricity usage for lighting goes in the winter down due to DST, energy usage for heating and cooling goes up, rendering the overall effect neutral. The researchers concluded that “the effects of daylight saving time on energy consumption are too small to justify the biannual time-shifting” (Havranek, Herman, and Irsova, 2016, p. 26).
Research shows that only 33% of Americans are in favor of continuing Daylight Saving Time. Most see it as an annoyance, and most proposed “benefits” turn into downfalls with a little investigation. More than 140 countries have adopted DST at some point, but about half have abolished it since. Will the United States be next?
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