Saturday 10 June 2023

The Smells of Summer

Sitting at my kitchen table on this sunny morning, I note that there's no longer any sunshine streaming into the house between the trees, as there was earlier in the year. The luxuriant foliage of trees in full leaf now blocks the rays until the sun finally ascends above the tree tops.

With trees, bushes and plants preparing to fruit, the country air has a specific summer smell. One that is always particularly magical to me, resonating with being on holiday, in a pine forest on a hot day,  caused by sunlight on conifers, rich in resins. The other is noted around sunset - and (far more rarely for me!) before sunrise.

The scent of a summer dawn or a summer dusk is quite different to what you'd sense in late autumn or early spring - the reversal of the photosynthesis cycle, as the stomata on leaves open for the day and close for the night, brings about a change in the smell of the air.

During daylight hours, plants are actively engaged in photosynthesis, through which they convert sunlight, carbon dioxide and water into energy-rich sugars. As a by-product of this process, plants release oxygen into the atmosphere as well as producing and emitting volatile organic compounds (VOCs), which serve to attract pollinators, repel herbivores, or communicate with other plants. Because VOCs evaporate more easily in warm temperatures, they are more noticeable in summer.

These olfactory difference are subtle but if you are attuned to them, you will observe how the smell of the country air changes over the day, and over the year.

Then of course there is petrichor - the smell that often accompanies the first rain after a dry spell, particularly when raindrops fall on dry soil or rocks. I felt this strongly this evening, when I was caught out by a sudden shower by Krężel station. 'Petrichor' comes from the Greek ('petra' = stone, and 'ichor', the fluid in the veins of the gods). It is a powerfully evocative smell arising a heavy raindrops hit dry ground, releasing plant oils, bacteria and VOCs. The moisture in the rain carries the scent through the air. Our noses are highly sensitive to these aromatic compounds; petrichor is earthy, fresh, and soothing. It is associated with a sense of renewal and nostalgia, familiarity, comfort and a connection with the natural world.

The seaside has its own associations, though I am far from the coast. Above all, the smell of damp towels, suntan lotion and salt water. I haven't been to the seaside for many years, but these smells I can conjure up quite easily.

These olfactory processes are all-important to the creation of qualia - the conscious experiences of being there. And they flash back - sometimes unbidden, but more usually prompted by a similar smell. And here, we are in Proustian territory - the smell of the madeleine biscuit which set off recollections of childhood in the author.

I am out in the garden with scissors and a colander, picking me some stinging nettles for lunch. The leaves are cut into strips for blanching on the pan. As I wander about the nettle patch, I take a long, deep sniff of the leaves in the colander. A sudden rush of memory - Northwick Park, Blockley, Gloucestershire. Polish scout-cub camp, mid 1960s. A walk to a nearby abandoned quarry. I'm seven at the time, away from my parents and enjoying it thoroughly. Along the path to the quarry, I experience stinging nettles in profusion for the first time; and yes - they do sting, you know about it for days (especially if wearing short trousers). The young brain quickly encodes the look of the plant - and the smell. It's not a particularly specific smell, but with my nose in the colander, I get that exact sensory flashback to that time and place. (I wrote about another olfactory flashback relating to Northwick Park back in 2010.)

Another one which grabs me every now and then is the smell of a plant (which sadly I can't identify), but whenever I do, it brings to mind a summer's day in the early 1960s.

I have just been given a die-cast Corgi toy (a Bedford van, in green Auxiliary Fire Service livery, with a ladder on the roof) by my parents. I am in the back garden of our Hanwell home, spinning around, the toy in my outstretched hand, racing to put out an imaginary fire. I can recall the sharp texture of the metal ladder on my fingertips. On the left hand side of the garden, looking from the house, is a bush, in flower, emitting a strong smell in the early evening, and I associate this smell with this toy van.

Another olfactory memory trigger is fennel (koper włoski) which I associate with our garden on Cleveland Road shortly after we've moved in.

Qualia memories are an intrinsic part of who I am; I feel them, I have trained myself to identify them and pin them down to a specific time and place. To me, qualia memories are my answer to the Hard Problem of Consciousness, and the reason why computers will never achieve true consciousness. Every time I have a qualia memory flashback, I am reminded that I am me and no one or nothing else; when those flashbacks come with similar intensity but from beyond my lifetime, I become more deeply convinced that consciousness is eternal. In the past week, I have had two such 'past-life flashbacks' directly generated by the smell of plants that I knew not in childhood, such as grapevines.

Experience summer through your nose, and let smells trigger memories...

No comments: