With the weather starting to warm and the days beginning to feel longer, it means one thing — daylight saving is almost upon us.
For many of us, it’s nearly time to change the clocks. But just what do you need to do, when, and why?
Here’s everything you need to know.
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When does daylight saving start?
On Sunday, October 6 at 2am local time, clocks will go forward by one hour in NSW, Victoria, ACT, Tasmania and South Australia.
In these states and territories, the first Sunday of October marks the return of Daylight Saving Time (DST).
Five out of eight Australian states and territories follow daylight saving — and that means, during summer, Australia has five time zones, rather than three.
On the flip side, daylight saving will end on Sunday, April 6, 2025 when at 3am clocks are turned backwards by one hour.
Who invented daylight saving – and what is its purpose?
A New Zealand bug collector is credited with coming up with the idea for daylight saving — although his initial idea in 1895 was for a two-hour time shift, Radio New Zealand (RNZ) reported.
According to RNZ, George Hudson wanted more daylight hours after his work shifts to collect insects.
He presented his idea to the Wellington Philosophical Society and eventually got support from MP Sir Thomas Kay Sidey.
In 1927, when Hudson was 60, New Zealand passed a law moving clocks forward an hour from the first Sunday in November until the first Sunday in March — although the move wasn’t very popular.
Around the world, other people had similar ideas. By 1907, British builder William Willett self-published a pamphlet advocating moving time forward in the summer so there was more time for recreation — and lower lighting costs — after the working day, according to the BBC.
Which Australian states don’t have daylight saving?
Australia, on the other hand, has a complicated history with daylight saving and not all states and territories recognise it.
Tasmania was the first Australian state to introduce daylight saving in 1916.
Throughout the 20th century, it was trialled, reintroduced and removed in different states and territories.
The current five states with daylight saving have observed the seasonal time changes since at least 1971, according to the Bureau of Meteorology.
But Queensland, Western Australia and the Northern Territory do not have daylight saving.
The issue continues to be debated almost every year in Queensland and Western Australia.
Why do some parts of Australia not have daylight saving?
There are pros and cons for daylight saving — and there is still discussion in some parts of the country over whether it’s a good idea.
Opponents point to a range of issues, including the difficulty for farmers who need to get up in the dark during daylight saving.
In October 2019, North Queensland MP Robbie Katter said daylight saving would place “an enormous burden on the livability and practicality” for people working in the region with an extra hour of work at a time of day when temperatures could soar above 40C.
“It’s hard enough already to entice people to live in remote areas of Queensland to fill roles in even our primary services,” he told the Sydney Morning Herald.
A 1992 referendum following a three-year daylight saving trial in Queensland returned a 54.5 per cent vote against introducing the measure permanently.
The issue has also been put to referendum four times in WA, most recently in 2009 when 54.6 per cent of people were against daylight saving.
Can daylight saving impact our sleep?
Australasian Chronobiology Society president Professor Sean Cain studies how circadian rhythms — the 24-hour cycle that our bodies, brains and behaviours are used to — are affected by changes such as daylight saving.
“We evolved over millions of years to get used to very bright days and very dark nights,” he told 7NEWS.com.au.
“So, our bodies are expecting these bright days and dark nights — it’s how we function best.”
Cain and the community of circadian researchers are strongly against daylight saving because of its negative impact on individuals, particularly when we lose sleep and “give ourselves a little bit of jet lag” when daylight saving kicks in.
The Society for Research on Biological Rhythms released a position paper in 2019 stating the benefits of living in standard time outweigh the advantages of switching between that and daylight saving.
Cain says switching between the two times is the most problematic part of the system. The drastic change happens in one day, and there is an expectation for people to adjust quickly.
“It is quite disruptive and it leads to more accidents, trips to the emergency room for heart attacks, things like that,” he said.
“We can say that this is 7 o’clock, or that’s 7 o’clock, but our bodies don’t care — they try to follow the solar day.”
Cain said the research shows people living in areas where daylight saving is not observed live longer, experience less illness and are more productive.
He said while many people support daylight saving and the extra daylight leisure time in summer, it was not justifiable for the health impacts on people.
“They associate daylight saving with summertime but they don’t understand the science,” Cain said.