Welcome Back to Standard Time

Posted on November 4, 2013


Ah… yesterday, Daylight Saving Time ended for the year and we all got an extra hour to sleep in.  Spring ahead, fall back.  I’ve never been a fan.  While stationed in the tropics (and in Arizona), I didn’t have to worry so much about which weekend the time change was coming, about oversleeping, that jet-lag-like feeling, or getting up in what seemed like the dead of night.  What I did have to keep in mind was that twice a year, I would have to mentally readjust the number of hours of time-zone difference between my location and my relatives, my bank, my colleagues in the US.

Why do we do this to ourselves?

I’ve long heard that this was all Ben Franklin’s idea, but actually the US didn’t institute the practice until World War I.  The idea was to save energy for wartime production efforts by taking advantage of the later daylight during summer months.  After the war, the US went back to regular time and we didn’t see Daylight Saving Time again until World War II.  FDR implemented year-round DST from 1942 to 1945, dubbing it “War Time.”  After the war, the US became a disjointed patchwork of DST here, standard time there, with no coordination to speak of, wreaking havoc with train, bus and broadcasting schedules.  Finally, Congress standardized the practice with the Uniform Time Act of 1966, and there have been only minor tweaks since then.

But does it work?  Does it save energy?

Not according to a nifty study done in Indiana when that state forced all of its counties to adopt DST in 2006 (before that, some counties used it and some didn’t).  The study, by University of California economics professor Matthew Kotchen and his PhD student Laura E. Grant,  concluded that Indiana households actually used more electricity after DST was adopted.  Why?  Possibly because “while the lighting costs were reduced in the afternoons by daylight saving, the greater heating costs in the mornings, and more use of air-conditioners on hot afternoons more than offset these savings.”

There is also a safety disadvantage to using DST.  Another study, by Michigan State University researchers Christopher Barnes and David Wagner, found increases in accident rates with the onset of DST in the spring.  And while they found no impact from switching back to standard time in the fall, other researchers have noted statistical spikes in accident rates associated with the switch back.  A Carnegie-Mellon University study calculating risk to pedestrians per mile walked, revealed a 186% spike in the risk of death between October and November annually, likely due to changes in sleep time coupled with earlier onset of darkness.

That’s the part I don’t quite understand.  Unless you live near the equator, summer days will be longer and winter days will be shorter.  What’s the point of shifting things around to (temporarily) give us more light in the morning, only to have more darkness in the early evening (or vice versa in the spring)?  The planet continues its march around the sun, and the daylight goes with it;  note that the farther toward the planetary poles you are, the more marked and rapid that effect will be.  In Maine, there are fewer than 9 hours of daylight at the Winter Solstice, but 15 hours and 20 minutes of light at the height of summer.  No amount of fiddling with clocks will give us more time in daylight or darkness; all it does is fiddle with our own internal rhythms and leave a lot of us feeling bleary and jet-lagged.

So if the studies are to be believed, and we save little or no energy while simultaneously experiencing more accidents and lost productivity… why are we still doing this?

Hopefully you enjoyed your extra hour of sleep… and be careful out there.