A Window to Wellness: Finding Calm in the Morning View — Epoche B2
A small suggestion, and the window it was tested at The suggestion of this essay is that before you look at your phone in the morning, you look out of the window for two minutes. That is the whole of it, and I have been testing it from my own kitchen window in Kokubunji, in western Tokyo, for about eight months. The reason for making a suggestion that small is that advice about well-being tends to arrive in large units. Take a holiday. Change careers. Start running. All of it may be sound, and none of it is available at half past five on a Tuesday morning, which is when most of us actually need something. What the sequence actually is, and why it runs that way Here is what two minutes involves at my window in October. The eastern sky above the neighbours' roofline is still the deep blue-black of night at five, and by half past it has gone grey; then, for perhaps ten minutes, the underside of the cloud turns orange and pink, and only afterwards does the sky settle into the pale blue that will last all day. The order matters, and I had it backwards for years — I had assumed the blue came first and warmed up. It is the other way round, and the reason is worth setting out, because the explanation is also the argument for standing there rather than reading about it. Start with the times, which have to be consistent for the rest to make sense. Astronomers divide the interval before sunrise by how far the sun still is below the horizon: astronomical twilight while it is between 18 and 12 degrees below, nautical between 12 and 6, civil between 6 and 0. Tokyo lies near 35.7 degrees north, and in mid-October the sun rises there at about a quarter to six. Civil twilight therefore begins somewhere around twenty past five and nautical twilight around ten to five — which is exactly the schedule I described: near-night at five, grey at half past, colour in the last ten minutes. Now the colour. Sunlight reaching an observer at dawn has travelled a very long way through the lower atmosphere, because it comes in almost horizontally. The standard measure is air mass, the length of the path expressed in multiples of the vertical thickness of the atmosphere; straight overhead it is 1, and at the horizon it is about 38. Along that path the air scatters light out of the beam, and it does so far more strongly at short wavelengths, the scattered intensity going roughly as $\lambda^{-4}$ for particles much smaller than the wavelength. Comparing blue at about 450 nm with red at about 700 nm gives a ratio of $$\left(\frac{700}{450}\right)^{4} \approx 5.9,$$ so blue is removed nearly six times as fast per unit of path. Over 38 air masses almost nothing short-wavelength survives, and what is left to fall on anything is orange and red. What it falls on, before sunrise, is cloud. A cloud at height $h$ can see the sun over the curve of the earth after an observer on the ground has lost it, by an angle $$\theta = \arccos\!\left(\frac{R}{R+h}\right) \approx \sqrt{\frac{2h}{R}},$$ with $R$ the earth's radius, about 6371 km. For a cloud base at 2 km this gives $\theta \approx 1.4^\circ$, and for cloud at 6 km about $2.5^\circ$. The sun's altitude near rising changes at roughly $15^\circ$ per hour multiplied by the cosine of the latitude, which at Kokubunji is about $12^\circ$ per hour, or a fifth of a degree per minute. So the cloud undersides are lit while the ground is not for something between seven and twelve minutes. That is the orange stage, and 'perhaps ten minutes' turns out to be right for the reason that the clouds over Tokyo in October are mostly a few kilometres up. The pale blue comes last because it is a different mechanism entirely. It is not light reaching us along a grazing path but light scattered towards us out of a short one, and short paths keep their blue — which is the same $\lambda^{-4}$ law running in the opposite direction. It cannot precede the orange, because it requires the sun to be up. Why the grey stage is grey That leaves the middle stage, and it is the one that made me claim you cannot learn this from a photograph. Between the near-dark and the colour there is a period lit only by light that has been scattered several times before reaching the ground, and it is very dim. The human retina has two systems, as Wyszecki and Stiles's standard treatment of colour science sets out: cones, which carry colour vision and need reasonable light, and rods, which are far more sensitive and carry no colour information at all. Below roughly a hundredth of a candela per square metre the cones have effectively stopped contributing and vision is entirely rod-driven, which means monochrome. The grey of half past five is therefore not a property of the sky. It is a property of the observer. A camera has no such transition. Its sensor responds the same way at every light level, and a long exposure at that hour returns a picture full of colour that no one present could have seen. This is the honest version of 'you have to stand there while it happens': the photograph is not a weaker record of the same thing but a record of something else. The rest of the inventory Below the sky, an ordinary inventory. Two crows on the power line, arguing, as they do every morning at this hour. A futon already hung over a balcony rail three houses down, which means the forecast is good and my neighbour has read it. The persimmon tree in the corner plot, which turned in the second week of the month and is now holding about forty orange fruit that nobody will pick. The 5:47 going west on the Chūō line, which I hear rather than see. At six the town's loudspeaker chime plays, and the street begins. None of this is beautiful in any way that would survive being described to a stranger. That is rather the point. The practice is not looking for something remarkable; it is giving the eye a task that has no outcome attached to it, at the one moment in the day before the outcomes start. Yohaku: the blank that is placed In ink painting there