Everyday Global: What is Daylight Saving Time, which the US Senate has voted to scrap?

Countries have long debated the usefulness of DST. In 2019, the European Parliament voted to scrap the custom, but later paused its coming into effect, which was scheduled for 2021. DST is currently followed by some 70 countries twice a year.

Why have Daylight Saving Time?

The key argument is that DST is meant to save energy. It involves resetting clocks ahead by an hour in spring, and behind by an hour in autumn, and those in favour of DST argue that it means a longer evening daytime. Individuals will complete their daily work routines an hour earlier, and that extra hour of daylight means — or is supposed to mean — a lower consumption of energy.

Written accounts suggest that a group of Canadians in Port Arthur (Ontario) were the first to adopt the practice on July 1, 1908, setting their clocks an hour ahead. Other parts of Canada followed suit.

In April 1916, during World War I, Germany and Austria introduced DST to minimise the use of artificial lighting. It gradually caught on in many countries. In the EU, clocks in the 28 member states move forward on the last Sunday in March and fall back on the last Sunday in October. India does not follow daylight saving time.

What is the problem with this?

In a recent article, Popular Science magazine cited studies to list out the disadvantages of DST. One hour of lost sleep in the US, one study calculated, increases the fatal crash rate by 5.4% to 7.6% for six days following the transition.

The New York Times report on the law passed by Senate started with a reference to the shortened sleep time: “After losing an hour of sleep over the weekend, members of the United States Senate returned to the Capitol this week a bit groggy and in a mood to put an end to all this frustrating clock-changing.”

Other studies found a higher rate of workplace injuries after the switch, leading to lost days of work; a slight drop in stock market performance; health problems as a result of disruption of the circadian rhythm (body clock) — and even longer sentences ordered by judges deprived of sleep.

The vote in European Parliament in 2019 followed a survey by the European Commission. Out of 4.6 million responses, 84% voted in favour of scrapping DST, The Guardian reported.

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