Sunday, 30 October 2011

Putting clocks back-and-forth - a pointless waste of human life


This ridiculous business of putting clocks backwards and forwards twice a year gets me more annoyed every time it happens.

It is so stupid that if it didn't already exist it would be utterly inexplicable, an exotic tribal custom.


The basic problem is that in the West we have adopted a work timetable of roughly 9-5 (09.00-17.00) which has three hours before noon and five hours after noon.

But to maximize the useful daylight we should arrange the working day so that (if you are on or near the longitudinal time line) noon falls in the middle of the working day with an equal amount of daylight either side.

This is, for most people, enough to get to and from work because the sun still cast a fair bit of light for a while before and after sunset (unless it is very cloudy).


But instead of changing the working day to fit with astronomical reality, we mess about with the clock.

British Summer Time puts the clock time forward, so that noon is at 13.00h, which means that the average working day is then equally distributed around noon - for an 8 hour day, four hours before noon, and four hours after.

We have this arrangement during 'summer' - but then the nonsense sets in. We reset the clocks to Greenwich Mean Time, as happened last night.


At extreme latitudes the different day lengths in summer and winter create problems. For example, I live at about 54 degrees North, and at the winter solstice there are only about 7 hours between sunrise and sunset; while at the summer solstice it is only fully dark for about 3 hours.

The summer has so many daylight hours that the clock change makes no significant impact. But in the winter, it really does become important to maximize the use of daylight. Yet we change the clocks such that noon falls less than halfway through the working day, and it is pitch dark by the time many people finish work.


And what about the timing of this change?

The Autumn Equinox is on 21 September, and we are by now only seven and a half weeks from the Winter Solstice (Dec 21) when the days are shortest.

By that logic, we should switch back to Summer Time seven or eight weeks after the Winter solstice - about 12 February.

But we don't. In fact we go back to BST on 25 March, which is after the Spring Equinox (21 March).

Please don't try to explain the logic behind this - because there is no sense in it.

Yet this is what everybody in Europe actually does: changes the clocks about 8 weeks before the Winter Solstice, and then restores them 13 weeks afterwards.


What I most hate about this business of changing the clocks - aside from the inconvenient waste of time, millions of man hours twice a year in England alone; and the disruption to circadian rhythms leading to sleep disturbances, which in the case of children may take a week or two to set right - is that the process distances us from astronomical reality.

If modern humans will not acknowledge the basic astronomical framework of the world we live in, and adjust human timetables to the timing of the rotation of the earth and the orbit around the sun of a tilted planet - but instead try to fit cosmology around our timetables by manipulation the measurement of time - then we are living in a world of dangerously extreme and irrational abstraction.

Which, of course, we are.