"Sekki is the traditional way of expressing seasons in Japan. There are 24 sekki, including rikka (立夏, the first day of summer) in early May, shoman (小満, lit. “a little full” as in growing, waxing) in late May and boshu (芒種, lit. bearded grain) in early June.

The 24 sekki can be further divided into three for a total of 72 shijijūni ko (七十二侯) that last for about five days each. These subseasons include mugi no toki itaru (麦秋至), or “the time for wheat has come,” which lasts from May 31 to June 5, and kamakiri shozu (“the mantis is born”) from June 6 to June 10. "

https://japantoday.com/category/features/lifestyle/just-how-...

The full list is here: https://en.wikipedia.org/wiki/Japanese_calendar#The_24_sekki

There used to be a maintained shared Google Calendar you could use that would display those in your agenda. While the names did not fit exactly with my local weather, it was interesting to give a name to small parts of the year. It felt very natural and intuitive.

I love this. Ever since moving back into the wild from the city, it's been so nice to take notice of all the little "microseasons" you'll see inside a usual season. I took it for granted as a kid, but as an adult, it's nice to name and partake in the various parts of the year as you mention.

It's common among many ancient cultures to treat equinoxes and solstices as events of great importance, as those mark the beginning of the season change, but not all regions experience seasons the same.

Ancient Egyptians, while knowledgeable of astronomy, had only three seasons: Akhet (summer/heat), Peret (flooding, of the Nile) and Shemu (harvest). Notice the conspicuous absence of winter.

https://egyptianstreets.com/2022/01/28/a-year-in-three-seaso...

In particular the traditional Persian new year (Nowruz) starts in spring, and is celebrated throughout central asia as far as Kazakhstan.

The roman calendar started the year in spring as well with March (hence the names September/October/November/December are literally the 7th/8th/9th/10th month). The Greek apparently were all over the place with the year starting in summer/fall/winter depending on region/polis.

Up until 1751 the legal year (fiscal year) in England (and its North American colonies) started at 25 March (Lady Day).

One origin story for April Fool's suggests that it's to do with getting the year wrong.

My understanding was that new years was always January, 1st, but that the year number changed on Lady Day

The UK's tax year still reflects this, starting from April 6, which both accounts (pun intended) for the year changing on Lady Day, and the transition from Julian to Gregorian calendars.

I'd heard this was because July and August (for Julius and Augustus) were added later to the calendar and originally there were only 10 months that started with January.

I believe those were merely renamed, and the original year was 10 months from March to December, with a nondescript “winter” period between December and March.

Oh, when it snows in Egypt (which it does do on occasion) they definitely notice the conspicuous absence of winter.

> Is anyone aware of a culture that did/does not have exactly 4 seasons?

Ancient Egyptian :-)

https://en.wikipedia.org/wiki/Egyptian_calendar:

“The ancient Egyptian calendar – a civil calendar – was a solar calendar with a 365-day year. The year consisted of three seasons of 120 days each, plus an intercalary month of five epagomenal days treated as outside of the year proper. Each season was divided into four months of 30 days.”

"There are just two seasons in the old Icelandic calendar: [...] summer and winter."

https://icelandmonitor.mbl.is/news/news/2015/10/21/do_you_kn...

The local version of this is: there are only two seasons in Michigan—winter and construction.

There were two in The Bay Area in the early 2000s: wet and dry. Prolonged drought has made us a one-season region, talking about four seasons like other areas.

So, a better calendar than ours :(

The Longest Year in Human History (46 B.C.E.) - https://youtu.be/fD-R35DSSZY gets into the "why the year we have is designed the way it is" ... though it takes 22 minutes to get to that part.

It wasn't really better as the 30 * 12 + 5 approach needed manual application of the + 5... which is what the new calendar was trying to avoid.

I gather +536 felt longer.

Another phenomenon I’ve found curious is the cross-cultural definition of a week as roughly a quarter moon, and correlated names for days of the week. [1]

  Sunday    Sun     Sōlis    Hēlíou     日曜日
  Monday    Moon    Lūnae    Selḗnēs    月曜日
  Tuesday   Mars    Mārtis   Áreōs      火曜日
  Wednesday Mercury Mercuriī Hermoû     水曜日
  Thursday  Jupiter Iovis    Diós       木曜日
  Friday    Venus   Veneris  Aphrodítēs 金曜日
  Saturday  Saturn  Sāturnī  Krónou     土曜日

[1]: https://en.wikipedia.org/wiki/Names_of_the_days_of_the_week

There's some ... but I think it misses two really important ones (and this is just off the top of my head):

1. The Romans had an eight day "week"; and,

2. The mesoamericans had a 260 day "week" (or, at best, interlocking 13 and 20 day "weeks").

I think the 7-day week is more of a statement about how effective the Judeo-Christian culture has imposed a modern week on the rest of the world.

> I think the 7-day week is more of a statement about how effective the Judeo-Christian culture has imposed a modern week on the rest of the world.

The 7-day week originated in Sumerian Babylon culture from 2100 BC and has to do with quartering moon phases. I worry when seeing many things attributed to "Judeo-Christian culture" which actually originated from other cultures, many aspects of what's in "Judeo-Christian culture" including perhaps some of the key stories in the Old Testament like the Flood appear to have been copied or at least inspired by stories from Sumerian culture which was considered the 'high culture' of the region.

They definitely didn’t invent it, but I would say it’s fair to give Christianity itself credit for converting Rome to a 7 day week & then most of the rest of the world after. It takes a religion with certain characteristics to accomplish that.

> it’s fair to give Christianity itself credit for converting Rome to a 7 day week

How so? Constantinus was the one who committed to the change and the day names were after the Roman Gods. Even today, we're using Viking names, like today happens to be Odin's Day, tomorrow's going to be Thor's Day and the day after is going to be Freya's Day. I'm not sure it is reasonable or rational to "credit Christianity itself".

Constantine adopted a 7 day calendar a few years after adopting Christianity. Christians had already adopted that calendar from Jews.

>The Romans had an eight day "week"; and,

The Beatles were Romans!

So were the B-52's, but only if you wanted to.

As far as I understand from the Wikipedia article, this practice has spread directly from Judaism (7 days) through Christianity through the Roman Empire (which renamed the days according to the planets/gods) to all of these places. It's not clear from the article if perhaps the Ancient Greeks had a similar system already - but otherwise, the Indians and the Chinese adopted this system from Roman/Hellenistic sources between the 3rd and 4th centuries CE, and other cultures around them adopted it from them slightly later.

Babylonians knew 7 planets and named each day of the week as ruled by a planet...

It had also been subdivided into planetary hours...

https://www.timeanddate.com/calendar/days/7-days-week.html

These are more jargon imports that came bundled with the 7-day week after the Romans, and then Europe, popularized it after adopting it. As an analogy, you don't hear many other ways of naming tea and coffee across cultures.

Polish doesn't use those names, but a different system:

Poniedziałek (lit. After not working) Wtorek (not sure) Środa (also not sure) Czwartek (lit. the fourth) Piątek (possibly means drinking day?) Sobota (not sure) Niedziela (Not working)

> Piątek (possibly means drinking day?)

The word means "the fifth day", from piąty (fifth) rather than pić (to drink).

Wtorek (Tuesday) comes from wtóry, meaning "second".

Środa (Wednesday) is from środa, meaning “middle”.

Sobota (Saturday) is from Hebrew שַׁבָּת‎ (šabbāṯ), meaning the Sabbath.

Oh yeah, I guess I was tired and didnt make the connection

‘Sobota’ resembles ‘sábado’ in Spanish and might refer to the Sabbath?

Wtorek probably means "the second day", and Środa means "middle". Piątek probably means "fifth".

Those all loosely resemble the Russian names, and as the other commentator noted “Sobota” sounds a lot like “Sabbath”

With some exceptions:

https://en.wikipedia.org/wiki/Pawukon_calendar

On Venus, a day is longer than a year.

I once heard Canadians in Winnipeg joke there were but two seasons, Winter and Construction. I think this was in reference to road maintenance.

In NZ these days I feel like we have two: Drought and Mudslide.

L.A. boasts of three seasons: Drought, mudslide, and wildfire.

That's hilarious. I lived with a really cold winter and it's not only road maintenance. If you have to do some renovations at your place they sometimes also need to happen on "construction" season, even if it's inside a lot of construction workers go to other places in the winter.

Actually it's 4: 1)Winter 2)More winter 3)Still winter and 4)Construction.

And also not exclusive to Winterpeg. It's used in many other parts of Canada as well. Construction season alternatively being named "orange cone season" as well as the roads are full of them.

I needed this today, thanks!

India (and nearby areas) famously used/uses 6 seasons. The Mayan Haab' isn't precisely a seasonal calendar, but each of the 20 'months' was used to much the same effect.

From my perspective, anything regularly periodic in nature is used to track time: the Sun (years, seasons, days, day/dusk) and Moon (months, weeks, King tides). Consider even the starfield (astrology: years, decades+).

Four seasons makes sense in all of these contexts, and I hypothesize that there are a lot of patterns in nature that are well bucketed into 4 sequential, equal seasons. This is impossible for me to demonstrate, unfortunately. Also, division by by 4 and 12, a year into four seasons is like a month into four weeks. Weeks seem to me to be among our most subjective fundamental time unit.

I see weeks as being the most arbitrary. I always like to imagine what life would be like if weeks were 3 days long. Or 11. I just love this topic.

I always wondered what it would feel like to not have weeks, or even years, but to live life in a continuous stream of days looking forward. I'm not sure if we would feel a horrible lack of closure or accomplishment, or if it would make us more productive and forward looking and moving. I wonder how much of my life I waste just trying to close out a week/month/year.

I was talking to a Jamaican primary school teacher once. She told me that the songs (Nursary rhymes) that they teach the kids are often based on old English ones ( like ring-ring-a-roses) but any reference to the four seasons have been mutated. Since in Jamaica they just have two seasons; wet season and dry season.

  > I always like to imagine what life would be like if weeks were 3 days long. Or 11. I just love this topic.

I especially like that you chose prime numbers. A week composed of a prime number of days will remain the smallest indivisible group of days that a culture will have.

Well, maybe, except that months are sometimes prime numbers and we subdivide them anyways, right?

I guess weeks don't exactly subdivide months, they're sort of separate systems?

Agreed, glad you called this out! I was thinking about rambling about this, but this is a topic I can go on and on about, and I was already off to a slow start today...

Please ramble! I've actually though much about this as well. It kind of forces a "holy day" because without one nothing fits into one week with any period other than "every day" or "every week" - be that week 5 or 7 or 11 days. I've heard that the seven day week was independently developed at least three times in ancient times across disparate cultures as well.

Australian indigenous people. Varying numbers of seasons, I'm guessing depending on the climate in which they live.

http://www.bom.gov.au/iwk/climate_culture/Indig_seasons.shtm...

Thailand has 3 seasons. Hot, cold and rainy season. The emerald buddha has three different sets of clothing to match the seasons.

https://en.m.wikipedia.org/wiki/Emerald_Buddha

I recently read about the Hindu seasons. Here is an off the cusp search result on the subject.

https://www.learnreligions.com/the-six-seasons-of-india-p2-1...

Apparently the Sami (Lapps) have/had 8 seasons.

https://www.amazon.co.uk/People-Eight-Seasons-story-Lapps/dp...

Indeed: https://www.samisiida.no/en/b/the-eight-sami-seasons

Do they have months as well? Once you get to 8 it seems like you could just as well call them long months than short seasons.

I can't think of an ancient Middle Eastern culture with 4 seasons. Hittites had 3, various Mesopotamian cultures had 2. It really only made sense in Europe to divide into 4.

Astronomically it seems to make the most sense, you have two solstices and two equinoxes dividing the year into four parts.

Can't we use Structured Equation Modeling or ML to cluster seasons based on actual data?

The Noongar of south western Australia denote six seasons: http://www.bom.gov.au/iwk/calendars/nyoongar.shtml

Makuru was much more suitable than “winter” for the climate in Perth: time to rug up and settle in for cosy nights with your loved ones. I wish the Noongar seasons were more often used in the south west of Australia by everybody, so much more suitable than European seasons shifted 6 months!

> Is anyone aware of a culture that did/does not have exactly 4 seasons?

Sub saharan people (and many Asian), have two seasons, rainy and dry.

Every place with wet season maybe?