Daylight Savings Time…a "what is?"

27 10 2008

It was a cold blistery Sunday, the morning of 26th October. I had woken up late as I am prone to do on any given Sunday except with one big difference. I had an extra hr of sleep even though I sleep for 10 hrs on Sunday mornings. …(yay me!). This is was actually the first time I had experienced the Daylight savings effects. (I initially thought it was the beginning of DST..but in fact it is the end of DST)…I now stand corrected Venkat 🙂

So I thought it would be a good idea to anyone traveling to DST affected (am I making this sound like an infection?) countries to understand what this is about and why its used.

Daylight savings time or DST or Summertime ended on the 26th of October (at least it did here in Netherlands).

DST was originally meant to increase the amount of sunlight in the afternoons during spring -summer to reduce the use of incandescent light (aka electricity) in the evenings. The clocks are then set back an hr during Autumn to change the time to Normal time.

How does it work?

At 2 AM every spring the clock jumps to 3 AM on the day the DST comes into effect. So effectively the first day of DST has 23 hrs.

Then at 2 AM in autumn on the first day of Normal time the clock is moved from 2 AM to 1 AM effectively having 25 hrs during the day.

Europe however shifts time at 1 AM.

Is it beneficial?

The original theory suggests that it would be, but the idea draws a lot of controversy…

according to Wikipedia

Adding daylight to afternoons benefits retailing, sports, and other activities that exploit sunlight after working hours, but causes problems for farming, entertainment and other occupations tied to the sun. Extra afternoon daylight reduces traffic fatalities; its effect on health and crime is less clear. Although an early goal of DST was to reduce evening usage of incandescent lighting, formerly a primary use of electricity, modern heating and cooling usage patterns greatly differ and research about how DST currently affects energy use is limited and contradictory.

Also most countries like the US for example change the time period of DST based on many factors (for ex. the US, based on Energy Policy act of 2005, changed the DST timings to ensure that almost 2/3rds of the year fell within the DST time zone.)

This creates huge issues when it comes to global transportation for example or medical devices..the affects are numerous. Some reports also suggest that its effects on human physiology may be quite substantial in the long run. Read here for this interesting angle.

If you want to know more about DST, its history, its effects and its implementation across the world you can read further in the links below:

Time and