Change for a Time

Why Daylight Savings in Tehran isn’t as good as it is in Mt. Shasta

© Bryan Zepp Jamieson
3/20/06
http://www.zeppscommentaries.com/Sociology/change.htm

During World War II, Great Britain had something called “Double War Time”. Come spring, the clocks were set forward by TWO hours, instead of the one most of us are used to. What it did was force everyone into going to bed shortly after sunset and get up at the crack of dawn. It doubtlessly saved a lot of energy in the industrial south of the island where the population was.

But a family friend was stationed in the islands north of Scotland, and he found the time change to be nothing but a pain in the ass. One day, sunrise would be about 6 am, and sunset about 6pm. The next day, sunrise was 8 am, and sunset 8pm, which brought on a form of jet lag.

Further, as spring wheeled toward summer, and the days got longer, he would find that sunrise might be about 5am, which wasn’t too unreasonable, but sunset was about midnight! Worse still, the long twilight characteristic of northern latitudes meant that it didn’t get full dark until about 1:30 am, and started getting light again about 3:30. So Double War Time or not, he was going to bed in full daylight, and waking up in full daylight. All the time change did for him was cause him to spend an extra two hours trying to get to sleep each “evening” while the sun lingered deep in the southwest. So he not only didn’t save any electricity from the time change, but found his normal diurnal cycle being messed with. It was counterproductive.

Go further north, and the time change becomes even more useless. North of the Arctic Circle there’s only a few weeks on each side of the equinox (spring and fall) when the time shift could play a significant role. But otherwise, what’s the point of changing the clocks if the sun doesn’t set (or in winter, rise)?

So the further from the equator you go, the less useful daylight savings time (let alone double war time) is. Therefore it must be extremely useful at the equator, right?

Wrong. At the equator, the days are always 12 hours long, and the nights are also 12 hours long, and there’s no significant seasonal variation. Nor is twilight much of a factor. The line between night and day (what astronomers call “the terminator”) is the same width at 80 north as it is on the equator, but objects on the equator blow through it at nearly 1,000 miles an hour, while an object at 80 north takes the same 24 hours to follow a circle with a much smaller circumference , [C = 2 pi r cos(80)] and so noodles through the terminator at about 180 miles an hour, give or take. At the equator, it gets dark just minutes after sunset. Boom.

The only places on earth where daylight savings time really does have a solid effect on human behavior, that causes a decline in energy usage, is between 35 and 55 degrees. About 90% of Americans, and, surprisingly, 90% of Canadians live in that band in the northern latitudes, which is why most of both countries have daylight savings time.

I know that personally, I like the time change because it means not having to wait so long for sunrise in the winter (I’ve never been keen on doing my morning stuff in the dark) and in the summer, I like the long evenings. But I’m at 39 north, which is nearly an ideal location.

Farmers claim they don’t like the time change because their livestock can’t adapt. Cows’ udders all explode, or something. Sounds messy. What the real problem is, of course, is that the FARMERS can’t adapt. They could simply slop the chickens at 7am instead of 6am when they go to daylight savings. But farmer Hiram is even more a creature of habit than his charges, and he can’t get a grip on doing something at 7 am instead of 6 am, even though it’s actually the same time of day. Mind you, the farmer is the one who is supposed to have the brain and thus be adaptable.

So: the closer to the equator or the poles you are, the less advantages to be gained from daylight savings time. Half-way in between is nearly optimal.

Now, if you’re wondering why I’m babbling about this, it’s due to an article an astute reader sent on to me today. It read:

“Iran's cabinet nullifies decision on daylight saving time.

“Tehran, March 19, IRNA-Iran's government spokesman Gholam-Hossein Elham said on Sunday that the cabinet nullified the decision on daylight saving time, which was ratified in 1991.”

[...]
“Elham said that the decision was initially ratified based upon concerns for daylight saving to reduce energy consumption. ‘However, specialized survey has not proved that change of time results in saving energy. Neither has any survey showed reduced energy consumption during the first half of the year once the change of time is effected.”’

Straddling 30 North, Iran would have gained minimal benefit from DST, but there is another factor: the climate.

It gets warmish in the summer. One hundred and twenty degrees, sometimes one hundred and thirty. Sometimes even hotter than that. Unofficial readings of one hundred and fifty-five (73 Celsius) have been reported.

But fortunately, the very hottest areas also tend to be desert. Which means that at sundown, temperatures drop fairly sharply. It doesn’t get COOL, exactly (lows might be about 85), but it’s at least not 120. It’s not like steamy cities in India, where the low might be 100, with 95 percent humidity. I don’t blame them for wanting to nuke their neighbors. I’d be grouchy, too.

Now, if you were living in Tehran, and you had to get up at 6 am, when would you want that big cool-off to occur? At eight thirty at night, or seven thirty? By forcing people to go to bed an hour earlier, DST was punishing anyone who finds it difficult to sleep in suffocating heat.

There was one other thing about the Iran announcement that struck me. The new rules for the time change go into effect IMMEDIATELY. They have to, because the time change goes into effect on the first day of spring, which this year is March 20th.

I can’t help but compare with the United States. Congress passed an emergency resolution extending day light savings time by three weeks (two weeks earlier in the spring, one week later in the fall) shortly after Katrina hit. Huge energy shortages were expected, and clearly, dramatic and drastic action was needed.

The change doesn’t go into effect until March 2007.

The Iranians decided the time change only caused confusion, and by eliminating it, eliminated the confusion.

I’m guessing that even with a year and a half warning, Americans won’t be so lucky, and there will be mass confusion here.

I just hope those Iranian farmers have enough brains to slop those poor chickens before their udders burst.