With the election of a politician in Western Australia (albeit on 98 votes) who campaigned solely on the introduction of daylight saving, is it time to start taking the issue seriously as a political force?
Probably not.
But it’s an interesting topic, and one with no shortage of strongly held views. Some people think it should be abolished, while others advocate for changes like shortening the daylight saving period, or just permanently moving the whole Australian Eastern Standard timezone (AEST) forwards by half an hour, and then removing daylight saving.
Here at Guardian Australia, my colleague Elias Visontay has suggested that we double daylight saving, or just shift the whole AEST timezone forwards by one hour.
So with all that in mind I’ve toiled deep into the code mines to produce a series of graphics that use sun position calculations to show how daylight saving currently affects daylight hours in Australia, and what would happen if things changed.
But first a disclaimer – working with timezones, daylight saving and dates in general is famously hard in programming. Also, did you know that the timezones database relied on by a huge number of computer systems is maintained by a handful of volunteers? It is!
So please – if you notice anything off in these graphics, let me know.
Firstly, here’s what daylight hours look like for each of Australia’s capital cities. This uses the estimated position of the sun at a given time and date, and does not take into account things like the weather.
When daylight saving kicks in, you can see the daylight hours being shifted forwards:
You can also toggle daylight saving off and on to see how it would change things in places such as Perth and Brisbane that don’t currently have it, or to compare the vastly different (potential) sunlight received at different times of the year in the north of the country versus the south of the country.
The most common argument in favour of daylight saving is how it makes daylight hours more available in the evening, typically after work.
For example Wilson Tucker, the new WA legislative council member and leader of the Daylight Saving party, told ABC radio in an interview: “There certainly are a few myths around daylight saving; I know historically people in regional areas have been opposed to it.
“We’re not adding any daylight here, we’re just aligning it with the afternoon where you can really appreciate it more,” he said.
For that reason the following maps compare the amount of daylight hours for each area within a given time period for different situations.
Here, with the date set to the middle of summer, you can clearly see how the daylight saving states have more daylight hours after 5pm, and non-daylight saving states and territories have more daylight hours in the morning:
WA stands out for having the fewest daylight hours in the evening, with only an hour of sunlight in the north-eastern parts of the state after 5pm.
In contrast, some parts of Victoria and Tasmania could potentially enjoy close to four hours of sunlight after 5pm, helped in part by the lower latitudes.
If daylight saving is added to the states and territories that currently don’t have it, then WA gets a much more even split of daylight between morning and evening, and other states and territories get more evening daylight hours:
And here is what it looks like if we abolish daylight saving entirely – the whole country shifts to more daylight in morning hours:
And finally, here’s a version of the map with all the options available.
You can switch between showing daylight hours within a given timeframe or show sunrise time instead; abolish daylight savings, keep the status quo, or apply it everywhere; show the results for the middle of winter (in which there is no DST), completely abolish Australia’s timezones and make everyone observe AEST (ideally this would be calibrated by turning Parliament House into a giant sundial); and the last option changes the map colour scaling to scale either between the states and territories or make the scale consistent between the various scenario options.
Notes and methods
- I used suncalc to work out the sun position for a given date and location, and for the map I created a hexagonal grid and then I used the centre location for the sun calculation. You can see the code behind the maps here, and the radial charts here.
- This blog by Andy Woodruff was the inspiration for my own maps.
- The election of Wilson Tucker, the Daylight Saving party politician, prompted the Labor government to introduce big changes to the electoral system. If you’re interested in what Tucker stands for besides campaigning for daylight saving, you can read his inaugural speech here in which he highlights housing affordability, closing the gap for Indigenous Australians, and a few other issues.
