Daylight saving (it's not savings) time: Why clocks are changed twice a year

Monday, 22 March 2021

It's that time of year when the clocks change, but why does this happen?

This story was first published in April 2021. It has been republished as daylight saving ends this weekend.

EXPLAINER: Daylight saving is about to begin. . Keith Lynch and Kate Newton outline the strange origins of shifting the clocks twice annually, and what a much more dramatic change would look like.

Early in 2021, a New Zealand lobbying group called Take Back The Clocks started a push for permanent daylight saving time – essentially moving the country time zone an hour forward.

The group launched a petition and its founder has hinted that a number of MPs may support submitting a private member’s bill, which one day could go before Parliament for a historic vote.

* Why daylight saving time could be bad for you

* It's high time we stopped mucking about with daylight saving

Daylight saving isn’t a partisan issue. If the bill were drawn, MPs would likely be free to make up their own minds on the topic. Take Back the Clocks believes it would have broad appeal and widespread support.

“Daylight saving clock changes are disruptive, unnatural and unnecessary. They stress all New Zealanders. There is not a single societal ailment that would not be helped by permanent daylight saving,” Louis Houlbrooke says.

The quote above was from 2021.

New Zealand has tinkered with its clocks. A lot. Could it happen again?

This is the history of daylight saving explained, why it matters, to whom it matters. Oh, and we mapped out what change would actually look.

The 101 of sleep and daylight saving (don’t call me savings) time

Let’s start with our circadian rhythms – the natural internal cycle that regulates our sleep-wake cycle or body clock over 24 hours.

Our own circadian rhythms are closely tied to light, or the day-night cycle. This is a complicated way of saying it’s hard to get out of bed when it’s dark. It’s hard to go to sleep when it’s bright.

The amount of daylight we experience depends on the seasons, which are a result of the earth’s tilt as it orbits the sun.

So when the South Pole is tilted towards the sun, it’s summer in New Zealand.

The seasons don’t mean much in the tropics, or near the earth’s equator. The amount of daylight and darkness is fairly consistent throughout the year.

The further north or south of the equator, the longer the days in summer and shorter in winter. Summer days in Dunedin are longer than those in Auckland.

Move the clocks an hour forward in Spring (Spring Forward, Fall Back is apparently a clever daylight saving memory trick), and people (assuming they work 9am to 5pm-like hours) have one less hour of daylight at the start of the day, and an extra hour after they clock off from work.

Moving the clocks doesn’t create extra sunlight. It only manipulates our own schedule.

The main purpose of daylight saving in New Zealand is to provide people with an additional hour in the evenings to have fun outdoors. This makes sense, particularly in summer.

The weird, messy history and inevitable Kiwi connection

In 1883, American railroad companies realised they needed everyone's watch to tell the same time or a lot of people would miss their train.

At the time, clocks wildly diverged, with different regions’ timekeeping based on when the sun rose or fell.

The International Meridian Conference of 1884 ultimately led to the world settling on defined time zones. This gave us a base. Then daylight saving came along and made a big old mess.

Kiwi postman George Vernon Hudson may just be the ideological father, or Karl Marx, of daylight saving time. He was one of the country’s leading entomologists and in 1885 presented a paper to the Wellington Philosophical Society where he suggested two hours of daylight saving, starting on October 1 for cricket, gardening, cycling or any other outdoor pursuit.

It has been reported that Hudson was frustrated he wasn’t getting enough time to go insect hunting after work.

It was not well received by his peers in the capital, with one critic saying calling the hours different would not make any difference, and it was “out of the question” to change a system that had been in place for thousands of years.

The idea was later picked up by an Englishman called William Willet (the great-great grandfather of Coldplay frontman Chris Martin), who may just have wanted more time to golf after work.

His 1907 pamphlet The Waste of Daylight suggested that “that at 2am on each of four Sunday mornings in April, standard time shall advance 20 minutes; and on each of four Sundays in September, shall recede 20 minutes”.

The yellow zones show daylight saving time in the US state of Arizona. You could take a long drive and potentially need to change your clock 11 times.

It picked up some support in the UK – even from Winston Churchill, who later boldly boasted he was one of its earliest supporters.

Daylight saving time became real when introduced by Germany in 1916 in a bid to save coal and energy during World War I. The British soon followed and the practice was up and running. The US adopted it in 1918, even though farmers were not at all keen.

The immediate effects? Well, US golf ball sales in 1918 – the first year of daylight saving – increased by 20 per cent, according to The Washington Post.

Since then, it has been dropped by some countries, adopted by others (or at least parts of others), been discontinued in some spots, extended elsewhere.

Right now, it’s fairly chaotic out there. About 70 countries have some sort of daylight saving in place. Japan, India and China don’t.

The West, however, seems to be gearing up for some sort of change.

For example, the European Union planned to stop changing its clocks in 2021, but an unholy mix of the Covid-19 pandemic and the EU’s plodding bureaucracy seems to have put the brakes on the plan.

(Interestingly, post-Brexit, Ireland and Northern Ireland could have ended up on different time zones.)

An aversion to shifting the clocks twice a year appears to be the only thing capable of building bridges in the deeply divided partisan US, with Democrats and Republicans uniting to propose the “Sunshine Protection Act of 2021”, which would make the land of the free the land of daylight saving all year round.

What about New Zealand?

New Zealand set a standard time in 1868 – 11 hours and 30 minutes ahead of the Greenwich Mean Time (GMT).

Tick that one off the list and move on? Not quite.

At the start of the 20th century, an Otago politician called Sir Thomas Sidey (who later served as Minister of Justice and Attorney General) began a hard push for daylight saving.

His idea: Move the clocks forward from September to March. His argument: An extra hour would allow Kiwis to be active in evenings, and save money on artificial light.

In 1927, the Summer Time Act was passed, instructing Kiwis to move their clocks forward by an hour between 6 November 1927 and 4 March 1928.

Other adjustments followed over the next decade or so – changing up the length of “summer time” and the time difference (it dropped to 30 minutes).

World War II prompted the Government to effectively introduce daylight saving the year around. This time (12 hours ahead of GMT) was adopted as standard time in 1946, meaning there was no more need for it.

The energy crisis of the 1970s, led to the introduction of the Time Act, and daylight saving time was brought back, this time one hour ahead of New Zealand standard time.

It was extended in the mid-1980s and again in 2007 after intense public debate and a petition to Parliament. We now have 27 weeks of daylight saving, from the last Sunday in September to the first Sunday in April.

The Chatham Islands, where it’s 45 minutes ahead of the rest of the country, also move clocks an hour forward in summer.

At the time, the Department of Internal Affairs (DIA) produced a fascinating report exploring the options.

The main purpose of daylight saving time, it stated, is to provide an additional hour for outdoor activities. The extension settled upon, it says, would avoid a clash with the fourth school term (going back to school and losing an hour sleep would be too hard for students) and benefit tourism by essentially extending the peak season.

There were concerns around businesses having to update their computer systems, but software updates post Y2K allayed these fears.

Interestingly, one option considered by bureaucrats was abolishing clock changes and instead adding half an hour to New Zealand standard time.

“This would avoid the twice-yearly change for daylight savings (eg, sleep desynchronosis and clashes with the fourth school term).”

But it would fail to take advantage of summer for recreation and make the mornings darker in winter. The option was not preferred.

A survey the following year found 82 per cent of New Zealanders approved of the 2007 extension. Farmers were a little less enthusiastic, with only 54 per cent approving.

My head is already hurting. Why does any of this matter?

Daylight saving does actually make a difference to our lives beyond losing a little sleep.

We’ll start with energy savings. The pro-daylight saving lobby have long pontificated on how it saves energy – the rationale being moving the clocks forward an hour when most of us are asleep reduces the demand for lights and heaters.

What about the curtains, mate? Joh Bjelke-Petersen was the longest-serving premier of Queensland.

This was touched on in DIA’s report which found “modest” savings of $500,000 in electricity costs for every week of daylight saving. But it suggested that the savings could easily be outweighed by more energy being used in the evenings and other impacts on transport use fuel.

There has been international research on this topic, with most failing to turn up any definitive answers.

So how about people’s health? Changing the clocks twice a year messes with our body clocks. This has an effect. Research suggests the change not only affects people’s mood and mental health, but it could lead to more heart attacks, strokes and car crashes.

Parents will passionately tell you they hate the clock changes as it’s harder to get kids to bed during the summer and tougher to get them up in winter.

Doing business – particularly with our friends across the Tasman – is potentially complicated by constant clock meddling. For example, daylight starts in Melbourne on October 3 but here on September 27. It is not observed in Queensland, the Northern Territory, Western Australia, Christmas Island or the Cocos (Keeling) Islands.

Never mind asking someone in the UK to join the call. Their “summer time” starts at the end of March and ends in late October, and they’ll almost certainly ignore the EU if it decides to end the clock tinkering.

Possibly both the most compelling and least compelling argument against daylight saving came from former Queensland premier Joh Bjelke-Petersen, who once warned that introducing an hour’s extra daylight would fade the curtains and carpets.

What would real change look like?

The series of graphs below illustrate what would happen if New Zealand were to bring in daylight saving all year round.

The first two graphs show sunset and sunrise times in Auckland and Dunedin. Together, the two cities offer a good representation of New Zealand as a whole, given the country’s latitudinal range.

The following two graphs outlines what life would be life for people getting up at 5am, 6am, 7am and 8am.

The bottom line: Year-round daylight saving time would mean darker mornings and a net benefit in daylight hours for those getting up a little later. The argument could also be made that daylight after a regular working day is more valuable than daylight in the morning.

What about the farmers?

In a 2015 piece for American news website Vox, journalist Joseph Stromberg argued for the introduction of permanent daylight saving. He wrote that while it was not ideal for farmers, it wouldn’t 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.”

Dairy farmers are up and working early. Like 4.30am early. They’re milking cows when most of us are still asleep.

There are about 8000 farm owners in the country, and 50,000 people working in the industry, according to dairy.co.nz data.

About 30 per cent of the country’s herds are in Waikato, where the sun rises at its earliest about 6am (in late December). Even in the middle of summer, dairy crews are working in the dark.

Wait. Just to be clear – I gain an hour?

You could ask: Should all of us have to endure reverting out of “summer time” because of 50,000 people, or one per cent of the population?

Federated Farmers Dairy chairman Wayne Langford says, in fact, the clock changes don’t really matter that much to farmers in 2021.

Sure, farmers are up early, but they’re well-used to working in the dark – a task that’s been made much easier by modern lighting tech.

If, hypothetically speaking, New Zealand was to introduce daylight saving all year around, would it matter?

Not really, Langford says. “We’re already working in the dark anyway. An extra half an hour really doesn’t make that much difference.

He also says farm work has changed. Workers aren’t doing a 12-14 hour day any longer. Farmers may well appreciate the extra time in the evenings.

Wilma Foster, Waikato regional leader for DairyNZ, holds a slightly different view, explaining most cows need to be milked twice a day in spring.

While cattle could be milked when it’s brighter, that would only mean farmers need to do the second round later in the evenings.

Her personal view is that more (of fulltime) daylight saving time may have a negative impact.

What next?

Maybe we'll see an MP decide to support this. Maybe we’ll see a members bill drawn. Maybe one day it’ll be dark in Dunedin at 9.30am in winter.

Maybe it won’t.

The DIA said in 2021 it is not aware of a groundswell of support for change and has no plans for further reviews of daylight saving.