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It’s time to make daylight saving time year-round

Let’s stop adjusting these, forever.
Let’s stop adjusting these, forever.
Let’s stop adjusting these, forever.
(Shutterstock.com)

Daylight saving time officially starts this year on Sunday, March 8, at 2 am. Everyone will need to remember to set their clocks forward one hour.

Unfortunately, doing so will create all sorts of problems. In the days following the change, researchers have found, rates of heart attacks, traffic accidents, and workplace injuries tend to increase slightly — likely the effect of millions of people’s bodies being forced to adjust to the missing hour of sleep. Workplace productivity, meanwhile, tends to decrease.

These problems have led some people, sick of changing their clocks twice a year, to call for the end of daylight saving. They point out that the practice doesn’t even appear to save any energy — one of its original purposes.

But the real solution here isn’t abolishing daylight saving. It’s making it a year-round affair. We should move our clocks forward one hour on Sunday and leave them there forever.

Why we shift our clocks back and forth

The simplest way of thinking of daylight saving time (DST) is that it’s a coordinated, official way of getting us to all wake up an hour earlier than we would otherwise — “saving” daylight, rather than sleeping through it. It means one hour less light in the mornings (before most of us go to work or school) and one extra hour of light in the evenings (after most of us are done and heading home).

Daylight saving time was first formally proposed way back in 1895 by a New Zealand entomologist named George Vernon Hudson, who realized that shifting clocks forward an hour would give him more time to collect insects in the evenings.

In the United States, the idea was formally adopted during World War I as part of an effort to save fuel, which was especially scarce. But it was only done during the summer — otherwise, farmers would have to wake up and begin farming in the dark to be on the same schedule as everyone else.

daylight saving poster

A World War I-era poster produced by a cigar company advocating daylight saving time. Retailers have supported DST because of the idea that it increases sales. (National Archives and Records Administration)

After the war, DST was abandoned, then adopted again during World War II (again to save fuel), then abandoned again by some states but kept by others, beginning and ending on irregular dates. Finally, in 1966, the federal government mandated that all states had to do summer daylight saving time — unless the whole state opted out — and specified the start and end dates.

The annual DST period has since been slightly lengthened a few times. Most recently, in 2005 — partly due to lobbying by the Chamber of Commerce, sporting goods manufacturers, and retailers that sell home improvement goods, among other groups — Congress extended the DST period by a few weeks at both the start and the end.

The big benefits of year-round daylight saving time

dst

Sweet, sweet sunlight. (Photo by Alexandro Auler/LatinContent/Getty Images)

Despite the fact that daylight saving time was introduced to save fuel, there isn’t strong evidence that the current system actually reduces energy use — or that making it year-round would do so, either. Studies that evaluate the energy impact of DST are mixed. It seems to reduce lighting use (and thus electricity consumption) slightly but may increase heating and AC use, as well as gas consumption. It’s probably fair to say that energy-wise, it’s a wash.

Looking at the lobbying groups in favor of DST, however, hints at the real benefit. DST means that people who work a standard day shift (and kids who go to school during the day) get more daylight after work. Manufacturers like this because we tend to engage in leisure activities, take short trips, and buy things after work — but not before — so a longer DST slightly increases sales.

For the same reason, a year-round DST would also be nice for anyone who works inside and simply likes to occasionally see the sun during the short days of winter. It’d mean getting up when it’s a bit darker out in exchange for an extra hour of light after work. In Washington, DC, for instance, sunsets in the dead of winter would be at roughly 6 pm, instead of 5, and sunrises would be at 8:30 am instead of 7:30.

DST boston

This chart shows how DST alters sunlight hours in Boston, Massachusetts. (SulalehFatehi)

The extra hour of morning darkness would be a sacrifice. But the extra hour of evening light would be a bigger benefit to all of us for the same reason that manufacturers like it: we’re much less likely to spend it inside, where we have artificial light either way.

Evidence can be found in the fact that primetime TV ratings sink noticeably whenever DST goes into effect, and in a recent study that showed children get more exercise on days with later sunsets, regardless of weather or school hours. This is why most people are looking forward to turning their clocks forward this weekend — they’d prefer to have sunlight after work, rather than before, especially during the shrinking days of winter.

Research also hints at a number of unrelated benefits of DST. For instance, one study found that rates of outdoor robberies declined significantly when DST was extended, after controlling for unrelated factors. The researchers’ hypothesis is that some crimes are more easily carried out during dark, and fewer people are going about their evening routines in the dark when DST is in effect.

Similarly, there’s evidence that a year-long DST might reduce traffic-related deaths, especially for pedestrians. On the whole, daylight saving means that more travel occurs during daylight, when it’s easier to see pedestrians, which is why researchers calculate that full-time DST could save a few hundred lives annually.

Finally, there’s another, simpler benefit to making DST year-round: It’s a hassle to switch your clocks and adjust to a new time twice a year. And, as mentioned, doing so appears to have real costs in terms of productivity and accident rates, as our bodies adjust to the missing hour of sleep.

The much smaller downside to making DST year-round

milking cows

These cows may have to get used to more milking in the dark. (Jean-Sebastien Evrard/AFP/Getty Images)

One particular group has been opposed to DST from the start: farmers.

Unlike most other workers, farmers can’t easily do some of their work when it’s dark out. This is the original reason DST is only in effect part of the year — because, due to the late-rising winter sun, year-round DST would mean it’d still be dark out when the clock says farmers should get up to work.

But there are also far fewer farmers than there used to be. In 1918, when daylight saving time went into effect in the US for the first time, farmers made up nearly 30 percent of the US population. Today, that number has dwindled to about 2 percent. So the compromise system we now have means that for 98 percent of the population, DST isn’t in effect during the part of the year when we’d benefit from it most.

agriculture workforce

Making DST permanent might not be ideal for farmers, but it wouldn’t actually force them to work in the dark. Instead, they’d start working with the sun in the exact same position in the sky, and clocks would display a different digit. Some of their work activities (say, buying supplies or shipping farm products) do need to occur on a set schedule during regular business hours, but it’s fair to assume they aren’t as locked into the 9-to-5 as office workers.

What’s more, many farmers have come to oppose the actual time shift, rather than DST itself. Dairy farmers, for instance, say the twice-annual shift forces them to move milking times, which can be difficult for cows. Permanent DST would solve this problem, too.

There is one entirely separate downside associated with year-round DST: Many schoolchildren would have to go to school in the dark, which is a bigger deal than adults going to work in the dark because many children wait for the bus on their own. However, this is just as much a result of the ungodly early hour most schools start at. My colleague Libby Nelson has the evidence that beginning the school day later would be beneficial for students’ grades and health.

The good news: We can actually do this

Lots of social problems are really hard to solve. There are often big, powerful players with a stake in keeping the status quo, or the actual solution is messy and hard to implement.

This isn’t the case with year-long DST. An act of Congress — just like the act that extended DST in 2005 — could instantly fix this problem, saving us the annoyance of switching our clocks and giving us more sunlight to enjoy during our leisure hours. Over time, even farmers’ opposition to DST has softened, and most people simply want to stop switching their clocks twice a year.

What’s more, huge swaths of the world already effectively follow daylight saving all the time. Because time zones have been altered and combined throughout history for the sake of convenience, lots of places set their clocks an hour or more ahead of solar time (which is based on the location of the sun). On the map below, everywhere that’s deep red is living in a DST world, year-round.

solar time map

This map shows the difference between local time and solar time. Red means that local time is behind solar time, the same as DST. Click to enlarge. (Stefano Maggiolo)

Let’s join them. Let’s make this weekend the last time we set our clocks forward — and let’s leave them there forever.

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