Spring Ahead? Why Daylight Savings Time is Dangerous

Pointless government tampering of natural world.

If you hate daylight saving time and the confusion and sleep deprivation it brings, you now have solid data on your side. A wave of new research is bolstering arguments against changing clocks twice a year.

The case for daylight saving time has been shaky for a while. The biannual time change was originally implemented to save energy. Yet dozens of studies around the world have found that changing the clocks has either minuscule or nonexistent effects on energy use. When Indiana finally implemented daylight saving in 2006, residents actually used more electricity.

Daylight saving time isn’t just a benign relic of the 1970s energy crisis. The latest research suggests the time change can be harmful to our health and cost us money. The effects are most disruptive in the spring and fall, right after time changes. Clocks in the US will spring forward this year on Sunday. Most of Europe moves to daylight saving time two weeks later.

The suffering of the spring time change begins with the loss of an hour of sleep. That might not seem like a big deal, but researchers have found it can be dangerous to mess with sleep schedules. Car accidents, strokes, and heart attacks spike in the days after the March time change. It turns out that judges, sleep deprived by daylight saving, impose harsher sentences.

clock_small Spring Ahead? Why Daylight Savings Time is Dangerous Health

‘‘Even mild changes to sleep patterns can affect human capital in significant ways,’’ Cornell University researchers Lawrence Jin and Nicolas Ziebarth wrote last year.

Some of the last defenders of daylight saving time have been a cluster of business groups who assume the change helps stimulate consumer spending. That’s not true either, according to recent analysis of 380 million bank and credit-card transactions by the JPMorgan Chase Institute.

The study compared Los Angeles with Phoenix in the 30 days after the March and November time changes. Arizona is a natural test case since it’s one of the two states, along with Hawaii, that doesn’t do daylight saving. In the spring, according to the consumer transaction data, the additional hour of evening daylight in Los Angeles managed to slightly boost card spending per person, compared with that in Phoenix, although by less than 1 percent. That spending uptick is swamped by the negative impact of the November time change, which sees the darkened population of Los Angeles spend 3.5 percent less at local retailers.

Daylight turns out to be a surprisingly large factor in how often workers stop at stores on their way home from their jobs in the evening. ‘‘At the end of the day, it’s either dark or light, and [people are] going to make an impulse decision at that point,’’ Diana Farrell, president and chief executive of the JPMorgan Chase Institute.

One possible explanation for the sharp spending decline, Farrell said, is that the extra hour of darkness could push more people to shop online rather than in-person. The study looked only at transactions via local retailers.

Daylight saving time may threaten our health, hurt local retailers, and otherwise disrupt our lives. But can anything be done about it?

As Hawaii and Arizona show, the US government gives states a choice as to whether to adopt daylight saving time. But states aren’t currently allowed to switch to daylight saving time year-round. Last year, 19 bills were pending in state legislatures around the US to end the biannual time change, according to the National Conference of State Legislatures. None passed.

Daylight saving is ‘‘an example of how sticky policy can be,’’ Farrell said.

A bill signed by Governor Charlie Baker in August included a provision establishing a task force to study if Massachusetts should leave Eastern Standard Time behind. The commission would analyze putting the state on Atlantic Standard Time throughout the year, rather than springing forward every March and falling back every November.

And since the beginning of the year, state legislators elsewhere have introduced an 20 bills on the topic, according to the National Conference of State Legislatures. Eleven bills, including proposals in Texas and California, would put states permanently on standard time; nine of the bills aim to make daylight saving time permanent, many of them by urging lawmakers in Washington to change the rules.

That looks unlikely. In a search of bills pending in the Congress this year and last year, none mention daylight saving.

  • DrArtaud

    Where would discussions of time be without a discussion of Standard Time. But let’s digress briefly. My wife and I took classes to be weather spotters, one held at a volunteer fire department, one done online using a computer and phone. Informal both, it gives basics on weather and dangerous weather. Come to find out that wind sheer had caused various airplane crashes. In order to address that, the National Weather Service was founded, and today, even non-fliers benefit by a system ever watchful for severe and changing weather.

    In a similar vein, Railroads were the impetus behind “Standard Time”. Cities and towns kept local time, determined when the sun reached a peak at Noon Time and crossed the meridian. But this passage of the sun was dependent on the longitude of your city. This gave Philadelphia, Harrisburg, and Pittsburgh different noon times, and that’s just in the state of Pennsylvania. Technically, the sun that crosses the meridan at 12:00 noon in Philadelphia wouldn’t cross the meridian until 12:06 in Harrisburg and 12:19 in Pittsburgh (using Philadelphia vantage). Railroads that determined track usage by time, and not by electrical signals developed later, experienced deadly accidents because of confusion over time. The solution was to create Standard Time within a zone. Of course, we don’t fool mother nature with this, look at the differences in sunrise / sunset times between these Pennsylvania cities for today’s date.

    6:18 A.M. Rise / 6:03 P.M. Set Philadelphia
    6:25 A.M. Rise / 6:10 P.M. Set Harrisburg
    6:37 A.M. Rise / 6:22 P.M. Set Pittsburgh

    But, it keeps things nice and uniform in the zone. Here’s a little more on the issue.

    Video: How did trains standardize time in the United States? - William Heuisler

    This time along the longitude thingy vexed sailors as well. Using a sextant, they could tell their latitude, how far north and south they were, but they couldn’t tell their longitude, how far east and west they were, and the inability to do that resulted in many deadly maritime catastrophes.

    If you have 3 hours and 15 minutes to spare, this is a wonderful show to watch on the trials and tribulations of determining longitude while at sea. The answer today, even before GPS, would be simple. Here’s the full movie, not a trailer. I bought the series on VHS (VHS, what’s that? LOL), and later DVD.

    Longitude (2000)

    Latitude and daylight. Those of us in colder northern climates enjoy a summer time benefit that few consider. Look at the difference between a near equator city vs one in northern U.S. mid summer.

    Caracas Venezuela
    6:12 A.M. Rise / 6:54 P.M. Set

    Bismark North Dakota
    5:15 A.M. Rise / 8:23 P.M. Set

    2 hours 26 minutes more daylight for the northern city. Yes! Further north means even more summer daylight. Of course, mid winter, it’s that much more darkness, but most recreation is done in the summer.

    Lastly, UTC. (Or GMT), I listen to shortwave radio. Since radio shows originate from a variety of cities around the globe, keeping track of the time shows start would be a task. To address this, broadcasters list their shows in Universal Time also known as Greenwich Mean Time. For Pittsburgh Standard Time we’re 5 hours behind UTC and during Daylight Savings Time we’re 4 hours behind. Other than that, if I see a show listed in UTC, it’s simple to know what time to listen. Reading for this comment, I see GMT is a Time Zone, and UTC a standard, but the difference is pedantic, they are one in the same.

    WBCQ Shortwave Schedule in UTC and Eastern Standard Time

    Military Time and UTC/GMT Times are written without colons and A.M. and P.M. are not used. 0000 is Midnight, 0100 is 1:00 A.M., 1730 is 5:30 P.M., etc.