Don’t Believe the Hype: Winter Did Not Begin Yesterday | Hacker News Reader

Don’t Believe the Hype: Winter Did Not Begin Yesterday

nautil.us

40 pointsdnetesn40 comments

Rest assured, those of us here in the southern hemisphere are not susceptible to that kind of hype.

In AU summer very much started (both officially and by popular understanding) 23 days ago - as it does every year - on the 1st of December.

Having seasons that match calendar months is terribly convenient. It also aligns with our experience of hot and cold -- January is typically the hottest month (the middle of the three summer months) and July is typically the coldest month (the middle of the three winter months). At least in the more populous urban areas of Straya.

The British approach of starting a season on the solstice / equinox has always seemed somewhere between weird and quaint (more towards the inconvenient end of weird).

Not least because the shortest / longest / median day varies drastically - I think up to 4 days variance? - depending on where we are in the leap year cycle, but also (IIRC) based on where you're standing in relation to the dateline.

I wonder what the appeal is of sticking to variant, non-calendar delineation of seasons? (I appreciate that's what the article attempts to explore .. but they don't seem to answer the question.) The author suggests January and July are the months with the most extreme temperature, so it presumably isn't related to any north / south hemisphere landmass disparity skewing temperatures.

What does anyone do that actually depends on the legally defined dates of the seasons?

I guess a stupid law might be written to follow the traditional definition rather than the weather, but that's about all I can think of.

There is a "winter truce" for evictions in France, but it runs from November 1st to March 31st.

> The British approach of starting a season on the solstice / equinox has always seemed somewhere between weird and quaint (more towards the inconvenient end of weird).

Surely the reasons for the definition of seasons was for farmers to know the position of earth relative to the sun so they could make good decisions about the likely weather for growing? To say it's weird is quite an extreme position to take, there are clearly rational reasons for it. Even if they're not as important to our society as they once were.

Perhaps, but I'm not so sure that was the reason for the definition.

For example, I know the dates of the solstices and equinoxes, and I'm (at best) a casual gardener. The fact those dates don't align with what I think of as the start of the seasons doesn't prevent me from remembering them.

In the location I do most of my growing, I'm actually more interested in tracking first and last frost - these are the primary constraints on many crops. These certainly don't align with equinoxes or solstices, let alone 1sts of months.

Farmers, presumably, are even more intimately aware of the usual dates (and variances) for these events in their region. That's why I don't think it was the reason for labelling the solstice / equinox as the start of each season.

Hi. I wrote the article. To tell you the truth, I've not (yet) found a reason why people in some places (it seems to be mainly North America and some in the UK) define seasons as beginning on solstices and equinoxes. Everyone just seems to repeat that that's when the seasons start, even if they acknowledge that there are other definitions.

I'd be curious if anyone finds a good explanation of why and how this definition took root!

I hypothesize that it is because we can predict the astronomical days centuries in advance, which in particular means that we can print calendars with "start of $SEASON" days on them with no fear that weather or something will contradict them.

I live in Michigan, which has a highly unstable climate. In practice as it happens right now, we're really more in "late Fall" than what we'd usually call "winter". Other years, winter has come in early November. Only the astronomical events are predictable in advance.

I offer as evidence the fact that the primary place I encounter these dates is on calendars. And once they are there, I think we have very little left to be explained; trusting words that appear to source from an authority even over the direct personal experience of our own eyes is a very common problem.

Cool! Though if you've searched exhaustively, I don't like our chances of finding anything. : )

Did you find anything that indicated a causal relationship against the astrological / zodiac - they mostly start/stop on 21st of months I think?

I'm not sure any of us are. In the US, summer is colloquially from the last Monday of May to the first Monday of September (Memorial-Labor Days). Many seasonal businesses use this definition for opening or extending hours. And it's within a week or two of what most schools do, too.

Calling the astronomical seasons illogical is quite a stretch. Sure, it's ~18 days off from the average weather patterns, but those can vary substantially from year to year, too. But everyone knows that. And folks are doing just fine.

The Memorial-Labor thing wasn't hard and fast, either. Growing up I remember it being either Memorial-Labor, all of May, June, July, and August, (I'm from Phoenix...) or "whenever I didn't have school".

In the US, the unofficial summer is Memorial to Labor day. Sure, as a kid you probably thing of summer as "not school." But most USians generally consider summer as between Memorial and Labor Day.

In which culture is this considered the "first day of winter"? English/US? I knew that the mid summer (longest day) was called "the first day of summer" in English and always though it was just an oddity in the language (like inflammable and flammable...)

The reason we celebrate christmas in late december is because old pagan mid-winter festivals used to be around this time. Sure the coldest winter weather is probably a month or so away still, but it's sure closer to the middle of the winter than the start, even if you count temperature and not sunlight?

Agreed, I've always thought of Winter as December, January, February. In fact I can't think I've ever had a discussion with anybody who seriously considered 21st as start of Winter, or late June as beginning of Summer. Seems like common sense.

Months are an arbitrary human invention which could be moved, while the solstice is fact.

What does that comment have to do with the discussion? The discussion is basically some say the season starts on the solstice, when actually the season appears to start several weeks prior. I've always wondered why the months are more in line with the solstices. But really the fact is the solstices are closer to the middle of the season than the beginning.

A few people were complaining that they land on the 21st... well it isn't hard to imagine moving over a week.

The seasons tend to run a month or two behind each solstice because of the great specific heat of water and proximity to the ocean, which I've described in other threads.

The summer solstice marks the beginning of summer astronomically just as the winter solstice marks the beginning of astronomical winter.

Midsummer is celebrated on the longest day in some cultures, on the solstice in others, but does not denote the middle of astronomical summer.

Meteorologic summer and winter currently begin weeks before the solstice. https://www.ncdc.noaa.gov/news/meteorological-versus-astrono... has a discussion on the difference.

That's exactly US/Canada definition. And winter solstice is "midwinter" in many European countries in fact.

So "astronomical summer" oddly starts with the day that the incoming solar energy is highest in the northern hemisphere? Ok, that explains why it's used in English, but really it just uses the same definition! The meteorological calendar just appears to use three months, so that is pretty arbitrary.

The most logical definition of astronomical summer and winter imho would have been winter and summer being the quarter-years centered on the summer and winter solstice respectively. Then the astronomical definitions would have been in line with (non-english) language, i.e. mid winter is the shortest day and mid summer is the longest day.

> Midsummer is celebrated on the longest day in some cultures, on the solstice in others

Aren't those the same thing (maybe give or take a day)? Where I live it's celebrated on a weekend near the solstice, which makes even more sense because alcohol.

> So "astronomical summer" oddly starts with the day that the incoming solar energy is highest in the northern hemisphere?

In a way, but you're looking at the effect, not the cause. The solstice is the day where either day or night is the shortest, which is caused by the earth either being at the aphelion or the perihelion (i.e. nearest or farthest points from the sun).

One could reasonably suspect that the solstice dates better represent a period just before the centre of the season rather than the beginning of it, since seasons take a bit of time to move in (at least up here in Canada). Snow won't stay until the ground has cooled enough, for example.

Aphelion and perihelion do not have anything to do with the solstices. They are currently coincidentally 2 weeks apart, but will be months apart in several thousand years.

http://www.timeanddate.com/astronomy/perihelion-aphelion-sol...

Surprisingly in Canada! Despite the fact than _normally_ in many places there is some/lof of snow by the first week of December Canadians keep insisting: nooooo - winter starts 21st December! Same oddity for summer.

So in a lot (most by area?) of Canada, people have been up to their arses in snow for a month, when they insist winter starts? Hilarious :)

I've always thought this was an (odd) US thing. I grew up in the UK and I never heard of "summer beginning on the solstice" until I moved to the US. Same for the winter solstice. I was always told in school that Christmas is an ancient midwinter festival -- the time when you expect to survive through the winter with the remaining food stores, since the days are lengthening.

Hmm, the author doesn't appear to realize that seasons lag the solstices/equinoxes by a month or more. This happens because the ocean soaks up the heat or cold... one of the properties of water. That's why we push them back half a season.

Whether your city is a maritime one or not is also a factor. For example, this year in California, summer went until the middle of October even though the sun was not very high at that point.

http://water.usgs.gov/edu/heat-capacity.html

I'm the author. (Hi!) The temperature extremes definitely do lag the solstices by around a month. That's not covered explicitly in the piece but implied when I say that the coldest quarter of the year (for the Northern Hemisphere) is from early Dec to early March, putting the temperature trough in the middle, in late January. That lag is well-represented in the meteorological seasons I suggest using: Dec-Feb (centered on January, the coldest month), Mar-May, etc.

Coastal California is indeed one of the few places in northern temperate latitudes where summer goes that late; some of Japan is in the same boat. Even so, December, January, and February are the coldest three months in SF, LA, and Tokyo, which supports the idea that meteorological winter makes a lot of sense. https://en.wikipedia.org/wiki/San_Francisco#Climate https://en.wikipedia.org/wiki/Los_Angeles#Climate https://en.wikipedia.org/wiki/Tokyo#Climate

Hi, well given that seasons are fuzzy, does it really matter whether the seasons start on the first or twenty first? If we really cared, I suppose another solution would be to move the months over a week or two.

Well, it's not like starting winter on December 1 isn't a lie as well – average "meteorological winter" starts Dec 8, a week later. The coldest quarter is also, of course, different every year, and not known until after the fact.

We use astronomical seasons instead because they are predictable, they are basically the same every year, and they definitively take place on a given date.

For the question of starting winter on the solstice vs halfway between solstice and equinox, we do get more cold weather after solstice than before. I think this is less important though – starting halfway between has made sense to me ever since I was a kid and learned what solstice and equinox meant.

A well-intentioned lie! Actually I'd call it more of an approximation. And the meteorological definition (Dec-Feb) is a better approximation of the coldest quarter than is starting the season on the solstice or on the cross-quarter day, in early November.

You cite predictability and definitiveness of starting the season on the solstice, but the meteorological season is better there, too.

Not actually, because in reality the coldest dates are different every year, and may change with global warming to boot. Start talking about meteorological seasons, and we can start arguing about what data to use. Does every climate region get their own definition of winter? Or do we use a one size fits all definition for an entire hemisphere? Do we go with an average of surface temperatures since they've been recorded, or do we use a running average of the last ten or twenty years? Do we use only surface temperatures, or should we take ocean temperatures into account as well?

And then you say, well, we'll just do an approximation and say Dec 1, but then you've chosen a truly arbitrary date that, again, is just as approximate to the "actual" meteorological date as Dec 22, and is off by close to the same amount.

Edit: because this post sounds pretty vehement, I just want to leaven it by saying that I recognize that all of these things are essentially arbitrary and this is not, in the end, a topic that is actually extremely important to me. I do think it's worthwhile to point out that the meteorological seasons are not as clearly better as this article makes them out to be. There are reasons for using astronomical winter, and they aren't really any worse than the reasons for using meteorological winter, as far as I can tell.

The author just doesn't understand the history of these concepts. The months really used to coincide with the begging of the seasons for traditional western calendars such as the Julian calendar, when it was introduced (it later became incorrect because seasonal drifts were not readjusted). It was the introduction of the Gregorian calendar that shifted dates, resulting in the beginning of seasons at the "wrong" date (the Gregorian calendar skipped dates on purpose). Since the Gregorian calendar autocorrects, this drift is not going away and we are stuck with seasons that start at around the 21st of the month. Defining the seasons according to the equinoxes is not only logical, it is the definition used for thousands of years it just turns out that our modern calendars don't respect these dates.

Author here. That's an interesting claim -- that the solstices and equinoxes used to fall on the first days of the month. (At least, I think that's what you're implying.) But I'm not sure that checks out: The Julian and Gregorian calendar diverge by 3 days every 400 hundred years. When the Gregorian calendar was adopted at various times in various countries, it skipped forward between 10 and 13 days (http://www.timeanddate.com/calendar/julian-gregorian-switch....). That's not enough days to explain why the equinoxes and solstices fall 20 or 21 days after the first of the month. Do you have a source for this?

Moreover, I argue that if you want to use astronomical seasons, it doesn't make much sense to begin them on the solstices and equinoxes -- they should begin near the "cross-quarter" days halfway in between (around the 7th of March, May, August, and November). And that is indeed how the seasons used to be defined in many cultures, such that Midsummer and Yule, the midwinter holiday, each came near the solstice.

This is not something that can be "proven" in the sense that all early calendars had drifts that had to be "manually" fixed over time. But we know that the Roman year started officially at the Spring equinox, so that was a calibration point [1]. The first serious attempt to fix the calendar was done by Julio Cesar, but by then he was stuck with the Winter Equinox at Dec 25th (our traditional date for Xmas). When the church introduced the Gregorian calendar their goal was to go back to the dates established for Easter around the year 300 CE, that's why they decided to jump ~10 days in the calendar.

[1] https://en.wikipedia.org/wiki/Roman_calendar#Calendar_of_Rom...

OK, the piece really isn't about how pre-Julian calendars defined the seasons or how and when they may have gone off the rails. It's an argument for why [1] meteorological seasons, starting a few weeks before the solstices/equinoxes, is the way to go, and [2] even if you are adamant about strictly astronomical seasons, beginning them on cross-quarter days makes more sense than the system we use now. One system used over 2,000 years ago doesn't figure into it.

I think this matches reality more closely:

  winter = dec,jan,feb
  spring = mar,apr,may
  summer = jun,jul,aug
  autumn = sep,okt,nov

Except, winter isn't really happening so far this year

In realities that have those months. :)

The etymology of 'winter', as best can be determined, is 'rainy season'. So depending upon your local climate you might like to slide those three-month windows around a bit.

In my part of the UK November is definitely part of winter on that basis, which is why I like the Soltice-as-midpoint-of-season approach.

Despite the fact that the author acknowledges that the solstice begins on different days, he has overlooked the fact winter the solstice for 2015 is TODAY (22nd), not the 21st.

So, the title is correct. ;-)

On a non-pedantic note, I agree that the seasons break emotionally well before their astronomical date. Winter beings with snowfall in November, Summer begins with the warm weather and long days in June (unless if you're living in Vancouver, in which case its still raining). And as widely as people seem to agree on this, at least in Canada, its easy to get corrected if it is "not actually [season]," yet.

Pedantic follow-up to pedantic note: The solstice was at 04:48 UTC on Tuesday, which is Monday night in the Americas [23:48 in ET, 20:48 PT, etc]. Everyone's right!

> "Japan’s traditional calendar also specifies a winter beginning in early November and ending in early February."

Actually like a lot of cultural things in Japan, this came from China. https://en.wikipedia.org/wiki/Solar_term

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