The September equinox (also known as the Southward equinox) is the moment when the Sun appears to cross what is called ‘the celestial equator’, heading southward. I don’t quite understand the phrase ‘the celestial equator’ but I am assured that it has to do with the planet’s axial tilt — currently about 23 degrees.
Usually when we speak of the ‘equinox’, we expect that on that day night and day will be of equal length. Whilst strictly speaking that is correct, it seems that the sunrise and sunset times given on metservice broadcasts don’t have night and day the same length on the day of the equinox. Typically, daytime seems to be around seven minutesthan twelve hours.
This is because sunrise is defined at the time the top limb of the sun is just visible on the horizon, and similarly sunset is defined when the top limb of the sun disappears below the horizon. Due to refraction of the atmosphere and the fact the sun is not just a point, the sun appears and disappears when its centre is slightly below the horizon. This explains the ‘extra’ daylight.
The common belief is that the equinox occurs on September 21, but that isn’t necessarily so. Due to differences between the calendar year and tropical year, the September equinox can occur at any time from the 21st to the 24th day of September. (The tropical year, it seems, is about 20 minutes shorter than the time it takes Earth to complete one full orbit around the Sun, as measured with respect to the fixed stars.)
I don’t know who works these things out but I am assured that this year the equinox occurred on the 23rd.
At the equinox, at the equator, the Sun rises directly in the east and sets directly in the west. Before the Southward equinox, the Sun rises and sets more to the north, and afterwards, it rises and sets more to the south.
Put simply, the equinox may be taken to mark the end of summer and the beginning of autumn (autumnal equinox) in the Northern Hemisphere, while marking the end of winter and the start of spring (vernal equinox) in the Southern Hemisphere.
Whilst few of us have anything like the knowledge that meteorologists have of these matters, we have, as we progress through life, become aware of weather patterns. I read an article recently in which doubt was cast on the concept of equinoctial gales but it has been my experience over many years that they do occur.
Living, as I do, quite exposed to the coast with little or no shelter from any wind that blows from the east and right around to the west, I am only too well aware of every puff of wind, from a gentle sea breeze right through to the more severe storms.
It was really very noticable from the weekend before last that the September equinox was at hand. On the Sunday I had to take down the sun umbrella that stood right through the summer, projecting from the centre of a heavy garden table. Though I remain hopeful that I shall enjoy a few more days using it, the garden furniture itself had to be moved to a more sheltered spot and in a short while it will either have to be taken indoors to a shed or garage or securely tied down. One night, about a week ago, I could hear noises from my back yard and on going to investigate found a small bin I use to collect glass for recycling blowing around. Clearly it is time to secure the outdoor ‘stuff’.
I am quite convinced that equinoctal storms are a real phenomenon. It is my experience that exceptionally frequent stormy conditions do occur around the equinox specifically and what might be considered the first ‘severe’ storm of the autumn does often appear around this time.
The reason seems to be that as storms start to track at latitudes further south, this is a consequence of the northern hemisphere cooling. To me it is fair — even obvious — to say that late September marks an increase in the frequency and severity of strong winds. As storm Ali moved on, leaving two dead, damaging property and leaving almost 200,000 without power, can we still doubt it?
Some people are afraid of thunder and lightning, others dread snow and frost, but it is wind that alarms me most. As I write this alongside a south-facing window in the run-up to the September equinox for 2018, there is a strong wind blowing outside. At a guess I would say it is up to force 6. Not quite a ‘gale’, which is force 8, but quite strong.
Despite my nervousness, it has its compensations, however, as I watch the antics of the birds, especially a flock of crows and separately, a small flock of seagulls. Their aeronautical manoeuvres are nothing short of amazing. It reminds me very strongly of how young children react to snow; they want to go outside and play with it and in it. The birds seem to be the same with the wind. They are riding the wind, as it were, catching the updraught and rising vertically without effort, soaring, diving and hovering. With barely a movement of their spread wings, they are chasing one another across the sky, performing loops and turns as they fly to a height, face into the wind and seem to stay there motionless. It reminds me of one of my very favourite books, Jonathan Livingston Seagull.
Hardly what one would call a book really; my edition is only about 80 pages and about 40 of those are illustrations. Written by Richard Bach, and illustrated by Russell Munson, it is a story about a seagull who is trying to learn about life and flight; striving for self-perfection. Originally a series of short stories published in the late 1960s, it was first published in book form in 1970 and by the end of 1972 over a million copies were in print. In 2014 the book was reissued aswith a 17-page fourth part added.
In the story, Jonathan Livingston Seagull is a young adventurous seagull bored with daily squabbles, among the flock of which he is a member, over food. He is passionate about flight and as he pushes himself beyond the normal recognised limits he is expelled by the elders of the flock because of his unwillingness to conform. Now an outcast, he persists in defying what were regarded as the limits, breaking through many, hitherto considered impossible, barriers.
One day, Jonathan meets two gulls who take him to a “higher plane of existence” in which there is a better world, found through perfection. There he meets another seagull who loves to fly. Then Jonathan befriends the wisest gull, Chiang, who takes him beyond his previous learning, teaching him how to move instantaneously to anywhere else in the Universe. The secret, Chiang says, is to “begin by knowing that you have already arrived”.
Failing to find fulfillment there, Jonathan returns to Earth to find others like him, to bring them his learning and spread his love for flight. His mission is successful and he gathers around him others who have been outlawed for not conforming.
Ultimately, the very first of his students, Fletcher Lynd Seagull, becomes a teacher in his own right and Jonathan leaves to teach other flocks.
I found the book most inspiring and I have recommended it to many people, especially young people who are struggling to break free from the frustration of boring normality.
If I had my way I would make this book an absolute must in the curriculum for the Junior Certificate, or even earlier.
Jonathan Livingston Seagull seems a long way from consideration of equinoctal storms but such, I guess, is the human mind, floating in the air, like Jonathan and following whatever air-current one gets into or like a wanderer who comes, like Robert Frost in his famous poem, The Road not Taken, to a junction where:
Two roads diverged in a yellow wood,
And sorry I could not travel both
And be one traveller, long I stood
And looked down one as far as I could
To where it bent in the undergrowth;
Then took the other, as just as fair,
Contact Michael at firstname.lastname@example.org