Seasons (again)

This is a bit of a repeat, since I almost forgot about writing this week. I decided to revisit the seasons thing.

English: Kukulkan at its finest during the Spr...
English: Kukulkan at its finest during the Spring Equinox. Chichen Itza Equinox March 2009. The famous descent of the snake at the temple. (Photo credit: Wikipedia)

We have just begun the season of Southern Hemisphere spring. This officially starts on 1st September and runs through to 1st December. Then summer starts and runs through to 1st March, then autumn runs through until 1st June, and winter extend to 1st September and the cycle repeats.

The reason that the seasons are defined like this goes back to 1780 when an organisation called “Societas Meteorologica Palatina” defined them as above. The organisation chose those dates because the seasons pretty much aligned with those dates in terms of temperature and rainfall and so on. The coldest three months in the Northern Hemisphere tended to be December, January and February, the warmest tended to be June, July and August, and so on.

The mute Hendrick Avercamp painted almost excl...
The mute Hendrick Avercamp painted almost exclusively winter scenes of crowds seen from some distance. (Photo credit: Wikipedia)

Since the seasons are reversed in the Southern Hemisphere, the southern cycle is as described above. We have Christmas on the beach and spend July wrapped up and close to any source of heat!

Astronomers do it differently. They divide the year into four seasons, but the seasons are not aligned climatically, but are defined relative to the Earth’s position in its orbit around the Sun.

English: Illustration shows the relative posit...
English: Illustration shows the relative positions and timing of solstice, equinox and seasons in relation to the Earth’s orbit around the sun. (Photo credit: Wikipedia)

Because the Earth’s axis is tilted relative to its orbit around the sun, the axis is be tilted towards the sun at one time of the year and away from it six months later. When the axis is tilted towards the sun, the sun is at its highest in the sky and more energy is received on Earth per square metre than at any other time of the year. It’s summer and warmer. When it is tilted away, the sun is at its lowest and we receive less energy than at any other time of the year. It’s winter and colder. (But read on).

On Earth, when the sun is high it is in the sky longer than when it is lower. The day is therefore longest and the night is the shortest in the yearly cycle. When the sun is midway between its highest and its lowest, the day and the night are of equal length.

English: Midnight Sun in Tromsø, seen from the...
English: Midnight Sun in Tromsø, seen from the old port. (Photo credit: Wikipedia)

The time when the sun is highest or lowest in the sky is called a “solstice“, either a winter solstice, or a summer solstice. The times when it is half way are called “equinoxes“, either an autumnal equinox or a vernal equinox, and the night and day are equal in length. These are the four main signposts of the seasons, as used by astronomers.

Strictly speaking, to say “Today is the summer solstice” or “Today is the autumnal equinox” are incorrect. Since the day and night lengths are changing all the time, the solstices and equinoxes are points in time, not whole days.

English: Two equinoxes are shown as the inters...
English: Two equinoxes are shown as the intersection of the ecliptic and celestial Ecuador, and the solstice’s times of the year in which the Sun reaches its maximum southern or northern position. Español: Se muestran los dos equinoccios como la intersección del ecuador celeste y la eclíptica, y los solsticios momentos del año en los que el Sol alcanza su máxima posición meridional o boreal. (Photo credit: Wikipedia)

There are four lesser known and less important signposts of the seasons, they are Beltane, Lughnasadh, Samhain and Imbolc. I’ve used the Gaelic names, but they correspond, in order, to the Christian festivals of May Day, Lammas, Halloween, and St Brigid’s Day. These all fall more or less halfway between the four main seasonal signposts.

Astronomically the Winter Solstice, which occurs around 21st December in the Northern Hemisphere. Many sources identify the date of the solstice as the beginning of winter. Similarly the Summer Solstice is identified as the start of summer, and the equinoxes are identified as the start of their respective seasons.

English: Beltane Fire Festival is an annual pa...
English: Beltane Fire Festival is an annual participatory arts event and ritual drama, held on April 30 on Calton Hill in Edinburgh. (Photo credit: Wikipedia)

This is odd, as the climatic seasons are usually considered to start three weeks earlier, with Northern Hemisphere winter climatically starting around the 1st December, and similarly for the other seasons. Starting the astronomical seasons on the 21st (or sometimes 22nd) of the month misses out 3 weeks or nearly a quarter of the season!

It’s also odd for another reason. The Northern Hemisphere winter solstice is when the sun is at its lowest point in its apparent position in the sky, so it is at its turning point in the cycle of the season and indeed the word “solstice” means “the point where the sun stands still”. It seems to me that this should be considered the mid point of the season, not the beginning of it.

English: Wheel of the Year with Fire Festivals...
English: Wheel of the Year with Fire Festivals and Quarter Festivals, Neopagan holidays: Yule, Imbolc, Ostara, Beltane, Litha, Lughnasadh, Mabon, Samhain (Photo credit: Wikipedia)

This is obviously true for the summer solstice too, and the equinoxes, being halfway between the solstices are add the mid points of the sun’s climb or descent to the solstices. They too also should be the mid points of their seasons, not the beginning points.

If the solstices and equinoxes are the middles of their seasons, where are the start end points then? Well, they would then coincide with the Gaelic or pagan festivals of Beltane, Lughnasadh, Samhain, and Imbolc! For example Beltane is about halfway between the Northern Hemisphere spring equinox and summer solstice on 1st May.

Original caption: Jack Frost Battles with The ...
Original caption: Jack Frost Battles with The Green Man at the Imbolc festival in 2008. Stendedge visitor center,Marsden, Huddersfield. (Photo credit: Wikipedia)

Although Beltane is a Gaelic or pagan festival and has mostly fallen out of favour, some cultures do celebrate the festival and some of the customs persist, such as the custom of dancing around a Maypole. Beltane and the other three similar festivals coincide with important agricultural events, such as sowing seeds and gathering in of harvests, so were of interest in earlier times.

However, if the astronomical seasons starts and ends were to be moved to coincide with the Gaelic festivals they would not coincide with the climatic seasons. The reason for this is that there is a seasonal shift because of the time that the seas and land take to warm up in spring and to cool down in winter. This pushes the climatic seasons back a few weeks and the start of climatic spring in the Northern Hemisphere is pushed back to about the 1st March and the same for all the other seasons.

English: Lammas growth on Quercus robur. Eglin...
English: Lammas growth on Quercus robur. Eglinton Country Park, (Photo credit: Wikipedia)

That’s why I think that the current idea of the astronomical seasons starting at the solstices and equinoxes is wrong! They should coincide with the Gaelic festivals instead, and then the astronomical and climatic seasons are related by the seasonal shift, instead of not being related properly at all.

Illumination of the earth during various seasons
Illumination of the earth during various seasons (Photo credit: Wikipedia)

Time waits for no man

English: Text: "You can't stop time... bu...
English: Text: “You can’t stop time… but you can turn it back one hour at 2 a.m. Oct. 28 when daylight-saving time ends and standard time begins.” (Photo credit: Wikipedia)

It’s approaching the equinox, that time of the year when the day and the night are of almost equal length. It’s the vernal or spring equinox here in the Southern Hemisphere, and the autumnal equinox in the Northern Hemisphere. For a number of reasons, the day and night are not of exactly equal length, and alternative definition is the time when the plane of the earth’s equator passes through the centre of the sun.

At around this time of the year many countries adjust their clocks to take advantage of the increasing daylight in the evening. Most countries who do this change their clocks forward in spring and back in the autumn, hence the mnemonic “spring forward, fall back”.

English: Winter,Spring,Summer,Fall? Such a glo...
English: Winter,Spring,Summer,Fall? Such a glorious Xmas day in Royston Vasey, it’s hard to tell which season it really is. Merry Christmas, one and all! (Photo credit: Wikipedia)

The reasons for the usage of “Daylight Saving Time” are debatable. The original intent was to align working day more accurately with the daylight hours while leaving more daylight time at the end of the day. Without Daylight Saving Time, people rose in the morning after an hour of usable daylight had occurred. It was during the two World Wars that “Daylight Saving Time” was first practised extensively in many countries.

Nowadays we are accustomed to “Daylight Saving Time”, and naturally there are dissenters who believe that it is unnecessary or counter productive. A farmer may point out that his cows don’t practise “Daylight Saving Time” and so the changes in the clocks are of no benefit to him, and can even cause him inconvenience.

An illustration of the end of Daylight Saving ...
An illustration of the end of Daylight Saving Time. (Photo credit: Wikipedia)

“Daylight Saving Time” is around one hundred years old, so it is a fairly recent invention. Indeed the synchronisation of clocks, even in a single country, is a recent phenomenon. Now we have clocks synchronised globally.

Computers have clocks. Indeed the very functioning of a computer requires a very accurate clock, so it should be no surprise that we take advantage of this requisite to extend computer clock usage outside of the computer itself.

"Saving Daylight^ "Set the clock ahe...
“Saving Daylight^ “Set the clock ahead one hour and win the war” uncle sam, your enemies have been up and are at… – NARA – 512689 (Photo credit: Wikipedia)

In the early days of computers, the clocks were not synchronised between computers. In fact that synchronisation had to wait for the development of networked computers. The people who used these isolated computers had to set the clocks manually, which was acceptable when computers were rare, but became a chore when computer usage started to climb and more desk had computers on them.

In a computer there are two sorts of clocks, a hardware clock and a software clock. The hardware clock is the fundamental clock in a computer system and it ticks thousands of times per second. If you’ve ever browsed the specs of a computer system you will likely have noticed the clock specification, the (these days) gigahertz rating. This is closely related to the clock speed, and the number of operations that the computer can perform in one second.

The original computers had speeds rated in kilohertz, so today’s computers are of the order of one thousand million time as fast as the old klunkers.

The software clock is related to the hardware and takes the clock information and translates it into a human usable date and time. It can’t do that without reference to the outside world as the hardware clock consists merely of a stream of “ticks” and doesn’t understand the concept of seconds, hours, days, months and days of the week. There is no weekend in the hardware clock’s world.


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The reference to the outside world in the early days of computing meant the operator typing in the time, and the software clock relating that to a tick of the hardware clock. From then on the software clock just counts ticks and works out the human usable date and time from that.

As computers started to be networked together, a problem arose. Computer A’s and computer B’s clocks will have been set by a human to as close as the human can manage, but they may be several seconds apart, a lifetime in computer terms. This can cause issues like money appearing in bank accounts before the money disappears from the sending account when the transaction is automated. All transactions are automated these days.

English: NTP client/server paradigm descriptio...
English: NTP client/server paradigm description Français : description du paradigme client/serveur NTP (Photo credit: Wikipedia)

At the same time as computers got networked, some far seeing people decided to set up a network of atomic clocks. These clocks are much more accurate than computers hardware clocks which can “drift”, because not all computer clocks tick at exactly the same rate. As a service this service is provided on the Internet and this has almost universally been adopted.

Your computer will contact a local time source, which contacts a less local time source, and so on until one of the top tier time sources is connected. Thus they all synchronise with the top tier time source. All the top tier sources synchronise with each other so eventually all computer clocks are synchronised.

English: In 1934 the first testcard "Tuni...
English: In 1934 the first testcard “Tuning Signals” was broadcast by BBC 1, the earliest being a simple line and circle broadcast using Baird’s 30 line system, and used to synchronise the mechanical scanning system. (Photo credit: Wikipedia)

A computer synchronises with its time source by basically sending a packet of data to its time source and the time source replies. The computer compares the times and repeats the process a few times to get an average, and then, since the packet has to go out and back, halves the average and estimates the time at the time source as the time sources knows it. Then it sets the hardware clock to match. It continually does this, constantly updating its clock as necessary, which gives a very accurate value for the local time.

One might question the necessity of this accuracy. Isn’t it being a bit pointless to set clocks with such nit-picking accuracy? In a news story which I can’t now track down, a financial organisation lost millions, maybe billions of dollars because they did not handle a “leap second” accurately. Automatic stock market trading programs made thousands of trades in the few milliseconds that the company was out of sync with the rest of the world. But to you or I, doing our “online banking”, it won’t matter.

English: clock brutally adjusted when a leap s...
English: clock brutally adjusted when a leap second is inserted Français : illustration d’une horloge qui est ajustée brutalement lors de l’insertion d’une seconde intercalaire (Photo credit: Wikipedia)

It’s worth remembering that the world-wide time system is pretty new. In these days we are accustomed to be able to contact someone on the other side of the world and to know what the time is with the contactee. But this is new.

It used to be the case that the local time was a sort of local consensus and did not rely on clocks. Then when clocks became more common the local reference time source was the clock in the spire of the church. Time was still local as the church clocks were not synchronised.

English: Clock on the roof of Our Lady of Dorm...
English: Clock on the roof of Our Lady of Dormition Melkite Greek Catholic Patriarchal Cathedral, Damascus, Syria Français : Horloge sur le toit de l’église du Patriarcat grec catholique à Damas, Syrie (Photo credit: Wikipedia)

As time keeping became more important, the local time zone might expand to cover  a time or a city. Clocks could be synchronised in a small area by use of travelling clocks or watches, and really accurate clocks and watches enabled the explorers from Europe to travel the world.

The advent of long distance travel (by the railways) and of telephonic communications resulted in the need for consistent time information across countries and across continents. However, standard time was only legislated in the United States in 1918, and this subsequently spread to the parts of the rest of the world that were not using Greenwich Mean Time.

A plate indicating the Greenwich meridian in S...
A plate indicating the Greenwich meridian in Stidia, Algeria. Photo taken in July 2005 by François Noël. (Photo credit: Wikipedia)

 

 

The Solstice Again

The Sun rising over Stonehenge on the morning ...
The Sun rising over Stonehenge on the morning of the summer solstice (21st June 2005). A crowd of between 14,000 and 19,000 people greeted the sun as it rose at 04:58 BST. (Photo credit: Wikipedia)

Today is the summer solstice in the Southern Hemisphere, the time when the sun is furthest south in the sky and hence at its highest. From here on in, the days get shorter as we slide back towards winter.

In the Northern Hemisphere,  it is of course the winter solstice, and those living there can expect the days to lengthen, as they move towards summer. Today is the Northern Hemisphere’s shortest day.

English: Daisy Rock's "solstice gap"...
English: Daisy Rock’s “solstice gap”” This shows the gap in the rock along which the sunset is viewed on the longest day. (Photo credit: Wikipedia)

Seasonal lag means that we can look forward to the warmest months of the year after the solstice, and those unfortunate enough to live in the Northern Hemisphere can look forward to a couple of their coldest months before things start to warm up.

I read somewhere that winter months are the months when people tend to put on weight and this was attributed to the fact that in winter, in the coldest weather people tend to exercise less and eat more. The reduced exercise is attributed to the tendency to stay home in the warm, by the fireside to avoid the often hostile weather.

Brooklyn Museum - Fireside Companion - Platt P...
Brooklyn Museum – Fireside Companion – Platt Powell Ryder – overall (Photo credit: Wikipedia)

And the eating more is because, well, what else is there to do but eat, when you are trapped by the weather. Our ancestors used to use up all the reserves that they had laid up for just this occasion, the hams and preserves, dried fruit and root vegetables and so on.

When the summer solstice happens, the weather is warmer and better, so people can get out an exercise, and, for our ancestors at least, agriculture kept them on the move, and the aim was to replenish the stores for the winter months, hence an emphasis on growing rather than eating. Besides, most crops would not be ready for harvesting.


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The winter solstice is one candidate for the start of the year. It marks a definite point in the cycle of the year. It’s after the solstice (a few months after the solstice) that things start growing again. The summer solstice is probably not a good choice as things are humming along then, ploughing and planting, growing and nurturing so it doesn’t really fit as the start of the year.

The spring or vernal equinox falls in March, around the 21st in the Northern Hemisphere. This is also a candidate for the start of the year, but to my mind, it is too late. Winter is tailing off at that time, things are starting to grow and because of the seasonal lag, it’s the start of spring. The year, are I see it, is already under way.


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Interestingly our fiscal year ends on 31st March. This is the date used by individuals to account for tax obligations. In many countries using the Gregorian calendar, the fiscal year ends on 31st December and almost aligns with the (winter) solstice based year. Other countries which use other calendars have fiscal years which relate to the local calendar.

As I have said the summer solstice in the Southern Hemisphere falls on 21st December (in most years). It is an astronomical point in time, not a whole day and can happen on 20th December. In the decade from 2010 to 2020 it falls on the 20th on three occasions.


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The summer solstice, Christmas Day, and the official 1st January New Year Day all fall within just over a week of each other. There is good reason to suspect historical links between these days, and there is much debate on the actual historical relationship between these events.

It is often said that early Christians adopted the winter solstice in the Northern Hemisphere, to squeeze out or replace a pagan celebration at that time. This may or may not be the case (or it may be partially true), but what is evident is that many cultures outside of the Tropics of Cancer and Capricorn celebrate a festival at around the time of the solstice.

World map with the intertropical zone highligh...
World map with the intertropical zone highlighted in red. (Photo credit: Wikipedia)

Between the two Tropics the sun is overhead twice in a year while the sun reaches a southerly point at the time of the southern solstice (winter in the north and summer in the south) and a northerly point at the time of the northern solstice, the hottest time occurs when the sun is overhead. This divides the year into unequal parts in these latitudes.

The climate of these regions is dependant on local conditions, such as whether or not the region is close to an ocean or is in the middle of a continent, and many tropical areas have wet and dry seasons, typically of unequal extents. One example know to many people outside the tropics is the monsoon season when a regions rainfall may predominantly happen.


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On the Arctic and Antarctic circle, at the solstices the sun just grazes the horizon at the summer solstice and the day lasts 24 hours. At the winter solstices the sun just barely reaches the horizon and the night lasts 24 hours. Closer to the poles the number of sunless days or days with the sum always above the horizon increase. At the poles the sun is below the horizon for three months and above it for three months. (I hope this is correct. I did research this a little, but I am not 100% sure).

Interestingly, I learnt recently that the sunset will continue to become later for the next few weeks. The reason for this according to the linked article is because we have tied our clocks to 24 hours exactly and the day is not exactly 24 hours long. Not only is it not exactly 24 hours, but its length varies during the year. In Wellington the sunset goes out to around 3 minutes to 9 and doesn’t dip below that time until 7th January 2015.

English: Sunrise at Winter Solstice (December ...
English: Sunrise at Winter Solstice (December 21, 2006 at 8 a.m.) as viewed through the doorway half way up Maiden Tower (Photo credit: Wikipedia)

(December data here, January data here).

While looking up these numbers I noticed that the day length in Auckland is nearly half an hour shorter up there. Also sunset is about a quarter of an hour later in Wellington meaning that when the summer weather finally arrives we will have an extra 14 minutes to enjoy the balmy evenings. That’s yet another reason to prefer Wellington over Auckland! We have more time to celebrate the solstice.

English: Wellington Harbour (New Zealand) view
English: Wellington Harbour (New Zealand) view (Photo credit: Wikipedia)

[Darn! I completed this on Monday but forgot to publish it. Better late than never, I guess!]

The Start of New Year

an old post card
an old post card (Photo credit: Wikipedia)

According to sources on the Internet, the winter solstice in the Southern Hemisphere occurs at 10:51 am UT on 21 June (this year, 2014). That translates to 10:51 pm in New Zealand. Just as in the Northern Hemisphere the start of the year corresponds roughly to the winter solstice  there, I like to think that the winter solstice in the Southern Hemisphere corresponds to the start of the year in the Southern Hemisphere. I don’t think that I would get much support to the start of the year officially changed, though!

The Earth at the start of the 4 (astronomical)...
The Earth at the start of the 4 (astronomical) seasons as seen from the south and ignoring the atmosphere (no clouds, no twilight). (Photo credit: Wikipedia)

The year can be divided into halves by the solstices, the winter solstice marking the sun’s most negative elevation with respect to the South Astronomical Pole since the previous June. From that moment in time the sun starts to move higher into the sky until, at or around 21 December, when the summer solstice occurs.

Midway between the solstices falls a time when the day and night are roughly equal in length. Around this time the sun crosses the celestial equator, and this time is called an equinox. There are two in the year, one when the sun is apparently moving south in the sky (the vernal equinox in the Southern Hemisphere) and one when it is moving north in the sky (the autumnal equinox in the Southern Hemisphere).

The Sun & the ecliptic rotation around the Ear...
The Sun & the ecliptic rotation around the Earth : The green Sun is the one of the vernal equinox (march), it is followed by a summer solstice Sun. Then automn equinox and winter solstice. The ground plane (latitude 50°N) is green, the rotating ecliptic plane is blue. Also represented are the celestial equator, the two tropics and the rotation axis. (Photo credit: Wikipedia)

Each of these quarter points of the year is or was celebrated with a festival of some sort, some of which, particularly the winter solstice were supposedly characterised by “unrestrained revelry“. The summer solstice was comparatively restrained, the vernal equinox was a celebration of new growth, and the autumnal equinox was a harvest festival, a gathering in and celebration of bounty produced by the year’s hard work.

What I wasn’t aware of is that there were other events called “Cross Quarter moments”. These are moments halfway between the equinoxes and solstices, and they are known as Embolc, Beltaine, Lughnasad, and Samhain. The Cross Quarter moments. the solstices and the equinoxes are set out in order for 2014 in the chart referenced here.

English: Wheel of the Year with Fire Festivals...
English: Wheel of the Year with Fire Festivals and Quarter Festivals, Neopagan holidays: Yule, Imbolc, Ostara, Beltane, Litha, Lughnasadh, Mabon, Samhain (Photo credit: Wikipedia)

Two of the Cross Quarter moments I have heard of, Beltane and Samhain. Beltane falls between the vernal equinox and the summer solstice and is roughly at the beginning of May, so corresponds roughly with May Day. It is astronomically the beginning of summer, but seasonal lag means that the season starts a little later than this.

English: Beer brewed during the night of Samha...
English: Beer brewed during the night of Samhain. Français : Bière brassée pendant la nuit de Samain. (Photo credit: Wikipedia)

Children (usually girls) still dance around the maypole or maytree, but few of them, and probably few of the adults have any idea of the origins of this ritual. Although it probably is related to Beltane or the start of summer, the significance and symbolism of the maypole is still debated. Some of the possible suggestions seem dubious and far-fetched, and I don’t think that is wrong to suggest that they reflect the prejudices of the people that make them. In particular it appears that Puritan Christians may have over-emphasised some aspects of the dance and celebration to argue for its banning.

English: Dance around the maypole during the M...
English: Dance around the maypole during the Midsummer celebration, in Åmmeberg, Sweden. (Photo credit: Wikipedia)

Morris dancing is also associated with a spring festival, usually Whitsun. It may possibly have been associated with Beltrane, but I don’t know the history of morris dancing, Whitsun and Beltrane or spring festivals in general well enough to assert this. There is a long tradition of ancient non-Christian rituals being adopted and given a Christian slant, so this may be possible.

Cotswold-style morris dancing in the grounds o...
Cotswold-style morris dancing in the grounds of Wells Cathedral, Wells, England — Exeter Morris Men (Photo credit: Wikipedia)

Samhain also has a long history and probably pre-dates Christianity. It is associated with the beginning of winter and marks the point where all crops are gathered and animals prepared for winter. Once again the Christian church has adopted the festival and the roots of “harvest festivals” are to be found in Samhain’s pre-Christian traditions.

English: A Donjari float used in Saijo's fall ...
English: A Donjari float used in Saijo’s fall harvest festival. I took this photo in October 2004. (Photo credit: Wikipedia)

The Christian church adopted the festival as All Saints (Hallows) Eve or Halloween. I note from the Wikipedia article that I linked to that some people consider that Halloween has no relationship with Samhain, but considering the similarities of the two traditions which happen at the same time of the year, I think that this seems unlikely.

Jack-o-lantern
Jack-o-lantern (Photo credit: Wikipedia)

Bonfires form a great part of the Samhain festival, maybe as an attempt to ward off the coming darkness of winter. I don’t think that it is a coincidence that there are still “celebrations” on 5 November, otherwise known as Guy Fawkes Day. An effigy of Guy Fawkes is burnt on a bonfire, in spite of the fact that Guy Fawkes was actually hanged.

All of the example above refer to the “Gaelic versions” of the various dates and festivals. It’s a bit simplistic to refer to a single “Gaelic version” as the dates and festivals have, naturally, changed over the years. Other cultures of course have their own versions of the various festivals. In the Tropics (between the Tropic of Cancer and the Tropic of Capricorn the sun is overhead at least once in the year, an obvious time for a festival!

English: Vector version of a design from the B...
English: Vector version of a design from the Book of Kells, fol. 29r. Traced outlines in black and white representing three intertwined dogs. (Photo credit: Wikipedia)

Since we have just passed the winter solstice, we can look forward to longer days and shorter nights from now until the summer solstice, which for us in the Southern Hemisphere comes around 21 December. So far this year winter has been fairly mild and a little wet. As we move towards the vernal equinox we still have the bulk of winter to come, as the astronomical year does not match the climatic year because of the seasonal lag.

English: Winter landscape off Ham Wall Somerse...
English: Winter landscape off Ham Wall Somerset. The most peaceful place on earth created from worked-out peat diggings. Excellent wetland habitat with characteristic reed beds. (Photo credit: Wikipedia)

Nevertheless it is a time to look forward and one can understand why the winter solstice is a such a time. It is a time of feasting, of using up some of the stores put away at the time of the autumnal equinox, the salted beef and cured hams. It is a time to relax, for mending and repairing, and for staying out of the weather as much as possible, as the weather of winter means that essential tasks only will be undertaken and the rush of springtime is still ahead. While the end of winter may bring shortages , it is still near the beginning and the stores are still full.

Russian Celebration Zakuski
Russian Celebration Zakuski (Photo credit: Wikipedia)

 

 

 

…for Christmas comes but once a year (Southern Style)

The Examination and Trial of Father Christmas,...
The Examination and Trial of Father Christmas, (1686), published shortly after Christmas was reinstated as a holy day in England. (Photo credit: Wikipedia)

“At Christmas play and make good cheer, for Christmas comes but once a year” said Tomas Tusser. Many people would rather it didn’t. Christmas is a time when stress levels go through the roof. People eat too much, drink too much and spend too much, meaning that January, a time when people traditionally go on summer holidays in this part of the world, is a time of dieting and financial restriction. Without careful planning the later part of the year around Christmas and the New Year can get very messy.

Another area of stress is in the receiving and giving of presents. Trying to decide who to buy for and what to buy for them is always difficult and many people resort to providing cash or vouchers or gift cards, and it still doesn’t remove all the issues. A card for a department store may be just what someone wanted, or it might languish in a drawer until it expires. Apparently by some estimates $2 billion of credit on gift cards goes unredeemed. But then again, a tie or socks might also be banished to the back of someone’s wardrobe.

20091226 - Christmas presents - misc - gift ca...
20091226 – Christmas presents – misc – gift cards – GEDC1240 (Photo credit: Rev. Xanatos Satanicos Bombasticos (ClintJCL))

The religious aspects of the holiday (“Holy Day”) are often ignored, and though thousands may gather for the “Carols in the Park”, few of those attending will go to church during the holiday. These aspects also exclude those of different religions, nominally, but many non-Christians celebrate some aspects of the holiday anyway, and gather for family time and exchange presents.

Christmas parties are a feature of the period before Christmas, and again, while one might think that those of other religions than Christianity would be excluded, office and private parties do not exclude non-Christians. In fact parties around this time of year are an opportunity for people to eat and drink and socialize and religion seldom figures.

English: Christmas is over 1 It must have been...
English: Christmas is over 1 It must have been some kind of party in Gillingham around New Year’s Eve 2010. (Photo credit: Wikipedia)

The secularisation of Christmas is both good and bad. Good, because it is not exclusive, but inclusive, and bad because it hides the traditional reasons for Christmas. But even within Christianity the reasons for Christmas are being lost – Christians buy Christmas trees and Christmas lights, and exchange presents, eat turkey and drink alcohol, all of which hark back to times before Christianity, to times often loosely called pagan.

Sunrise over Stonehenge on the summer solstice...
Sunrise over Stonehenge on the summer solstice, 21 June 2005 (Photo credit: Wikipedia)

Indeed it is often said that Christmas is when it is simply to align with the so-called pagan festivals of mid-winter that celebrate the solstice. The winter solstice marks the time of year when the sun reaches its lowest point of the year and is closely related to the shortest day. Of course in this hemisphere the solstice is the summer one, and the sun is at its highest, so the day is the longest one. This usually happens around 21st of December.

English: Musicians on Sydney Harbour during 20...
English: Musicians on Sydney Harbour during 2001 Xmas holidays. (Photo credit: Wikipedia)

The traditional northern hemisphere Christmas is in mid-winter, more or less, and the traditional fare is heavy mid-winter fuel of turkey with stuffing, vegetables including potatoes, with gravy and followed by heavy fruit pudding and mince pies.  In the southern hemisphere the solstice is, as I said, the summer one, and, really, the traditional fare is probably unsuited to the climate. The southern hemisphere is developing a tradition of holding a barbecue for Christmas dinner, thereby replacing the turkey with steak and the heavy root vegetables of the northern hemisphere with salad and the Christmas pudding with ice cream. The heavy room temperature ales favoured north of the Equator are often replaced by lighter chilled beer and lager.

New Years 2010-2011
New Years 2010-2011 (Photo credit: russelljsmith)

Some of the more modern symbols of Christmas northern hemisphere style have received a southern hemisphere make-over. Santa is still a fat old man with a beard, but his clothing is often changed to, more suitable for the climate, board shorts, though they will still be in the “traditional” Coca-Cola red, and even on the surfboard he will likely retain the floppy hat. The reindeer are, at least in Australia, replaced by kangaroos.

Santa Claus, Christmas Parade, Lambton Quay
Santa Claus, Christmas Parade, Lambton Quay (Photo credit: Velvet Android)

Southern hemisphere cities tend to put on “Santa Parades”. I don’t know if this happens much in northern cities, though I do see a website for a Santa parade in Toronto. It seems to me that the weather would be better in the southern cities! Strangely the big man, who always brings the end to the parade in the last float, usually wears the full regalia of red suit, boots, and cap. He must swelter!

This has been a rather unstructured look at Christmas with an emphasis on the southern hemisphere celebrations where they differ from the northern version of the same. All that remains is for me to wish anyone who stumbles across my blog a Merry Christmas and a Happy New Year.

Ngā mihi o te wā me te Tau Hou.

Pohutakawa
Pohutakawa (Photo credit: StormyDog)

Summer, Autumn, Winter and Spring

Revolving earth at winter solstice on the nort...
Northern winter solstice

On 21st June we in the Southern Hemisphere get our shortest day of the year. This corresponds to the longest day in the Northern Hemisphere of course, and my wall calendar, which originates from the Northern half of the planet says that 21st June is the start of summer. I believe that the official start of winter, here in New Zealand, is 1st June.

That started me thinking. One would expect that 21st June, the southern winter solstice, would be the middle on winter, since the earth is tilted furthest away from the sun in southern latitudes at that date, and that the seasons would change mid way between the solstices and the equinoxes in both hemispheres for similar reasons. The equinoxes are the days when the night and days are the same length in both the northern and southern hemispheres. (Pedants will notice that I’m not being precisely correct in my explanations of equinoxes and solstices, but that doesn’t matter for my purposes.)

English: Two equinoxes are shown as the inters...
Equinoxes

It is obvious to anyone who has reached a sufficient age that the warmest and coldest parts of the year don’t correspond to the solstices and that the change from higher than average temperatures to lower than average temperatures and vice versa don’t happen at the equinoxes, though these latter events are probably not that noticeable. There is obviously some seasonal lag.

Image representing Wikipedia as depicted in Cr...

So I browsed to Wikipedia, which is a useful place to start, even if some people question its accuracy and veracity. I’ve not found it too bad, myself. Sure enough, there is an article on seasonal lag, and I’ve no reason to doubt the information there. To summarise, the authors of the article attribute the lag to the oceans which, because of the latent heat of their water absorb heat energy and release energy as the seasons change. I’m not sure that I completely understand the reasons for this, but there are undoubtedly deeper analyses on the Internet. The Wikipedia article contains one reference.

Apparently the seasonal lag is different in each half of the year. I believe that means that the four seasons are not all equal in length. Hmm, summer does seem shorter than the other seasons, but that may be only subjective. However, our shortest day is only four weeks away, so we will at least be seeing more daylight each day from then on. We will be on the upwards slide to Spring and Summer, even though Winter will not have bottomed out, and we can look forward to barbecues and a summertime Christmas!

Pohutakawa
Pohutakawa flowers. They bloom at Christmas, in early summer.