This weekend, the UK and Ireland will put the clocks back by one hour and revert to GMT for the next five months. We do this every year – and it’s completely bonkers.
By moving our clocks back to GMT we move the middle of our daylight hours to mid-day. This is, therefore, back to natural time. The sun is at its highest point in the sky at 12 noon. When we were an agrarian society, this made perfect sense. People got up earlier and, in the absence of artificial light, went to bed when it got dark. The middle of their day was therefore around 12 noon.
Nowadays this makes no sense at all. Most people work around a core 9am – 5pm day. Most of us work longer than this but the hours at each end are probably evenly distributed. 1pm is therefore closer to the middle of most people’s working day than 12 noon. When it comes to their waking day, 12 noon is probably only a third of the way through. Even an early riser who, say, got up at 5am and went to bed at 9pm, the middle of their day would still be 1pm. Shifting the middle of our daylight hours to 12 noon means that for almost everyone, there will be light in the morning when they don’t need it and darkness in the evening when they do.
Research by Cambridge University bears this out. The graph below shows the amount of human activity during a winter day. As we can see, just by moving the light area forward by an hour (which is what would happen if we left the clocks where they were) a lot more of that activity takes place in daylight.
The report notes that for much of the winter some 35% of the population is asleep at sunrise. The results of sleeping during daylight and consigning so much of our activity to the darkness can be seen in the rapid increase in accident statistics and energy consumption once the clocks go back.
It is true that, if we stuck with BST all winter, December mornings would be particularly grim. The sun would not rise in London until around 9am and in Inverness until 10am. But for much of the rest of the winter it we would trade the morning daylight we don’t need for evening daylight, when most of us are far more active. Even in Inverness, the December trade-off would be for a 4.30pm sunset instead of the 3.30pm one they get at the moment. Overall, throughout the country, a later sunrise and sunset would increase the amount of activity we do during the hours of daylight, thus reducing the number of accidents and lowering our energy consumption.
Greenwich Mean Time, with the mid-point of its daylight at 12 noon, suited the rhythms of our agrarian past. British Summer Time, with its mid-point at 1pm is far better suited to the working and leisure patterns of the modern world. Let’s leave the middle of the day at 1pm. It suits us far better. Please let this be the last year that we plunge ourselves pointlessly into the darkness.
Update: The government has just announced that it is considering moving UK time forward by one hour for three-year trial period. It needs the devolved governments to agree first though.