Next weekend, most of the country will be reverting back to Standard Time. This is occurring approximately 54 days before the Winter Solstice (Dec 21). In the Spring, Daylight savings time is implemented in the first weekend of April (approximately 102 days after the Winter Solstice. Obviously, the beginning and ending of daylight savings time is not determined by the sun’s position in the sky but by something else but I have not been able to figure out what it could be. Anyone got a clue? BTW I like daylight savings time and would like to begin something the last weekend in February. Maybe I should write my congresswoman.
It’s very simple, the beginning and end of DST are determined by law. Congress wrote the law (1975?) and the president signed it. Prior to 1974, DST did not start until the last Sunday in April. In 1974, it started in January.
I think Cecil covered it, but I am too lazy to look. It has always been a political decision, not astronomical. It started in WWI to conserve energy, and people liked it. You get to enjoy an extra hour of sun at night, and the sun does not come up at an outrageously early hours, which in some European cities like London would be at about 3 a.m.
I think it has to do with seasonal temperature lag.
It’s still relatively warm for the month after the Autumnal Equinox, certainly warmer than the month before Vernal Equinox, even though both do get the same amount of sunshine per day. So people would still like it to be somewhat sunny in the evenings in October. But by November, it’s too cold to do outdoor activities in the evening, so it might as well be dark.
http://www.straightdope.com/classics/a5_052.html
http://www.straightdope.com/classics/a910906.html
And don’t forget, boys and girls, it’s Daylight saving time, not savings
Thanks for the replies and the link to Cecil’s DST columns.
This particular tidbit from Cecil’s Column:
Dear Cecil:
As a farmer, I resent being called an idiot. The reason we are against daylight saving time is that our crops can’t stand the extra hour of sun in the dry part of the year. They burn up and wilt. --J. Bass, Dallas, Texas
Dear J.:
This is a joke, right?
A co-worker actually asked earlier this year why February got the extra day in Leap Year. She thought the extra day should go in July when it was warmer. I almost lost it.
I have always been skeptical of the claim that manipulating our clocks somehow saves energy. Perhaps it was true in the early 1900’s when our society was more agrarian, but I doubt it. If it is true, there should be a measurable difference at the electric power plants. Does anyone who works at a power plant know of any hard evidence to support this idea?
cooldude Sunrise in London at 03.00?? I think you jest.
OK, it’s more like 3:50 am on Midsummer morn, but you still get cooldude’s point. Actually, with daylight saving (or British Summer Time), sunrise there is pushed back to 4:50, which gives a little more “night” before daybreak, but without the time change, sunrise would be at ten minutes befor 4:00 and on a clear morning at that latitude, the eastern sky will be pretty bright ar 3:00 UTC.
Leeds is 200 miles north of London and our sunrinse in summer is slightly earlier but up there in Scotland the differance is more significant.
In WWI they actually had double daylight saving where the clocks were changed by as much as two hours.In those days the grid was not developed so the best possible use of natural light was made to keep industry running for the war effort.
Yeah and we wash our hair in sunrinse too for that glowing shine!
notfrommensa says: << This is a joke, right? >>
Man, I hope so, but one never knows. Some of the mail that Cecil gets… you just keep hoping the writer is deliberately putting on, but.
Does England still convert to summer-time on a different date from continental Europe? There was one year when the UK, US, and Europe all changed on the same weekend… but most years, it’s different, and there’s about a two-week period every fall and spring when I go buggy from trying to figure out the time difference. Lesse, we moved ahead an hour but they didn’t, so… do I add or subtract?
I don’t know if this is intentional or coincidence, but first-weekend-in-April to last-weekend-in-October very neatly covers the professional baseball season. All life revolves around baseball, right?
“notfrommensa”
::slaps thigh::
…cool name.
I’m just grateful that they don’t switch back to Standard Time any later than they do now. I have a hard time waking up when it’s still dark. In Southern California, sunrise isn’t until 7 am. Ugh.
Why did they put daylight savings time into effect in the winter of 73-74?
It qwas surreal being in school while it was black outsdie!
It was the midst of the energy crisis of the 1970’s. I guess it was supposed to provide more daylight during the evenings to save energy. All I remember was walking to school when it was very dark. IIRC, the sun didn’t rise until around 8 during December.
Thanks, samclem. I was going to post a reminder if no one else did.
I looked at http://www.intellicast.com at various cities to see who had the latest sunrise. To list a few:
Tallahassee, FL 7:45 AM
Erie, PA 7:46 AM
Cincinnati, OH 7:57 AM
Point Barrow, Alaska, would beat any of these towns, but it’s a special case.
The real question here is this: Why does DST last LONGER than Standard time? It seems like that would make DST the standard time, and standard time a change from the norm. Pretty stupid if you ask me. What I like is in fall when there’s 2 times for day. An infant could be born at 2:45 AM, October 29, 2000, and die at 2:05 AM, October 29, 2000. Odd, huh? (Yes, I know they’d use the EDT, EST designations…and I know that it’s PDT, etc elsewhere).
Jman