After the gloom of winter, the brightness of summer evenings seems like the light of life itself
The bright, long evenings of summer! The best, the most optimistic season of the year is the trio of months when the evenings are getting brighter and brighter and those suffering from SAD - seasonal affective disorder - shrug off the symptoms associated with winter melancholy.
It's not the cold, or the rain, of winter that triggers SAD, it's the darkness. So, how enlightened, literally, of Pieta House to name their inspiring annual walk for those affected by suicide, Darkness Into Light.
It is light that lightens the mood, and the light of early summer seems like the light of life itself.
There's a difference of about 20 minutes in the sun's light between London and Dublin, and another difference of, I'd say, 15 minutes between Dublin and Galway. Clocks in Britain and Ireland were fully harmonised around the years of the First World War - you can't have accurate train timetables unless 9.30am means the same time to everyone on the schedule.
But even before 1916, there was some resistance to aligning Ireland formally with Britain. For reasons not entirely clear, the Catholic church campaigned to retain "Irish time" as a separate entity. Possibly the church was picking up on a more nationalist mood, possibly to affirm a sense of accordance with nature, since nature's time was God's time. Maybe it seemed anti-modern to campaign against the rules of the clock.
Yet Ireland is fortunate - and the west of Ireland most fortunate of all - to have this wonderful season of light and long evenings, where, on a good day, the twilight lasts until near 11 at night. There's even a poetic name for it, the Celtic Twilight or, in Scotland, what they call the 'gloaming'.
If climate contributes to character, then the ability to relax, to take your ease, to be laid-back, so characteristic of the west coast of Ireland, may well be linked with the long evenings and the soft twilights.
Light lifts our mood, and yet I wouldn't want the 24-hour daylight they experience in Iceland and in the Arctic Circle summer. Sleepless in Tromso? I have been, with the eerie presence of a full daylight at 3am. Reykjavik in June can be full-on partying and groups of boozy women roaming the streets in the wee small hours. I don't blame them - they have to live through winter's 24-hour darkness to get to 24-hour light. If climate shapes character, then the violent darkness of the Scandi noir genre fits their winter personality.
The sunnier the climate, the sunnier the personality? Virginia Woolf thought so, eulogising Italians for their extrovert disposition, formed by their weather. The more the climate allows you to live in the street, she thought, the more friendly and cheerful you are. The English would be less introverted and reserved if they had fewer grey skies and more sunshine, but they might also place less emphasis on moderation and compromise, described as virtues of moderate climes.
Twilight disappears the nearer you get to the equator, and it's astonishing, in Africa, when the sun comes down like a sudden shutter. One moment you're in daylight, the next it's night. It's unfair to generalise about a whole continent, but in his brilliant book on nature's imperatives, Prisoners of Geography, Tim Marshall suggests that Africa's climate has often been its true darkness, facilitating so many tropical diseases. Geography is destiny, and the way the light operates within that parameter is crucial to our environment.
Light has such an impact on psychic mood that light therapy is now sometimes prescribed for people who suffer from SAD. But too much artificial light can disturb the circadian rhythms - the inner bodyclock which accords with the earth's rotation. A Harvard study has shown that blue light - the light that's transmitted by electronic devices and even energy-efficient lightbulbs - is unhealthy with overuse, possibly contributing to cancer, heart disease, diabetes, and, of course, insomnia. We're now told not to sleep in a room with artificial lights twinkling in the corner, and not to use electronic devices after 10pm.
The research into sleep claims that the solar day - the one ruled by the sun - is still vital to our psyche. Not so daft to be in accord with nature, maybe.
No wonder we start the year by looking forward to the stretch in the evenings, heralding the lengthening of the solar day. No wonder pagan and nature-worshipping religions were focused on the summer solstice, Midsummer Day - June 20 or 21 by the sun's measure, but usually marked around June 24, St John's Day in the Christian calendar. And no wonder Midsummer is so big in Sweden and Finland, with huge bonfires being lit in a symbolic effort to persuade the sun to stay at its solstice peak. No wonder people can go a little wild at Midsummer.
We wish the bright mornings and long evenings of early summer could go on forever. But we know that even as the days lengthen, soon they will begin their cycle in the opposite direction. As Robert Herrick put it in the 16th century: "The glorious lamp of heaven, the sun/The higher he's a-getting/The sooner will his race be run/And nearer he's to setting." Gather ye rosebuds of light while ye may.