Summertime
Depending on where you live on this earth, pretty soon you have to adjust your clock an hour forward, or backward. And lots of people never know which one it is. And they therefor can not answer the more important question haunting that weekend: can we, or can we not, sleep an hour longer this sunday?
It seems to be a mystery, but it is really not that hard to think trough.
Fist, a general mis understanding seems to be that it is about saving daylight during the winter, but that is not true, its about saving daylight during the summer period.
On a normal day, at 12:00h the sun is at its highest in the sky, and at 00:00h the sun is at its lowest (right beneath your feet). This makes the day symmetrical at the 12 o'clocks: if the sun comes up 8 hours after 00:00h, then it also goes down 8 hours before 00:00h, so sunrise is at 08:00h and sundown is at 16:00h.
But what if the sun comes up at 04:00h? Then it goes down 4 hours before 00:00h, so at 20:00h. So it rises very early in the morning, but it also sets pretty early in the night.
Most people won't even dare to think about rising at 04:00h, but lots are still active at 20:00h; The first hours of the day are wasted, while in the last hours are spend in darkness.
This is where daylight savings time, or summertime, comes in. We shift the day one hour forward. The sun rises at 05:00h, at 13:00h it is at its highest, and it sets at 21:00h, and 01:00h is the darkest of the night. The day becomes symmetrical around the 1 o'clocks.
The shift happens in the spring, you wake at 10:00h in the morning, but it is actually already 11:00h. So you get to sleep an hour less. Lets just wait for that weekend in october, that is when we shift back and we get to sleep an hour longer!
Remember
So remember: days are symmetrical where 00:00h is the absolute midnight. But in the summer this means the sun rises early and sets early. Nobody is there to enjoy those early sunbeams, so we shift the day by an hour, making everything happen an hour later. Sunrise happens an hour later, and the evening is prolonged by one hour.
Or: *spring forward, fall back*. Incase you cannot remember the above, this one is an easy way to remember that in the spring you have to adjust your clock by setting it one hour forward. Which equals to one hour of less sleep ...
When do we switch?
For the EU (European Union) countries this is the last weekend in march and the last in october. In the US the beginning is mostly a week later then in the EU. But as of 2007 the US is switching to the second weekend in March and the first weekend in November.
Other issues
- The exact midnight depends on your countries time-zone relative to the real center of that time-zone.
- In more tropical regions there is no need to summertime because its always summer there! Well no, because the difference between winter and summer sunsets and sunrises are not so large, and by far not enough to justify the concept of changing the time twice per year.
Last modified: 2007-11-19 20:15 GMT