Clocks in Europe just went back an hour, those in the US will do so on Nov 3. What’s happening?

What is the change with respect to Indian time?

Now that DST has ended in Europe and clocks have gone back an hour, the time difference between London and India is five and a half hours (and that between Paris or Berlin and India is four and a half hours). Britain is now on Greenwich Mean Time (GMT); until Saturday when it was on DST or British Summer Time (BST), the time difference between London and India was four and a half hours (three and a half hours for Paris or Berlin).

But what’s the point of having Daylight Saving Time?

DST is in use during the period from spring to autumn (or fall), when Europe and the United States get an extra hour of daylight in the evening.

No daylight is of course, actually ‘saved’ — rather, the idea is to make better use of daylight. So when it is autumn (or fall) in the Northern Hemisphere, and days are typically beginning to become shorter and nights longer, clocks are moved back an hour as governments decide to in effect transfer an hour of daylight from evening to morning, when it is assumed to be of greater use to most people.

Dates for this switch, which happens twice a year (in the spring and autumn) are decided beforehand. By law, the 28 member states of the European Union switch together — moving forward on the last Sunday of March and falling back on the last Sunday in October.

In the US, clocks go back on the first Sunday of November. Russia experimented with having permanent DST in 2011, but that created a situation in which it was dark at midday at some places, so in 2014, it returned to switching from DST to standard time in the autumn.

When did the system of putting clocks forward and back start?

The idea of fixing clocks to save energy and to make the day seem longer than it is, is over 200 years old, but its sustained implementation took longer.

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, with Europe facing severe coal shortages, Germany and Austria-Hungary introduced DST to minimise the use of artificial lighting. Many other countries on both the warring sides followed suit. The US introduced it in May 1916, and has stuck with it ever since.

However, the move was in the end, only a ruse — and several European countries dropped it after the War ended in 1918. The practice returned again during the energy crises of the 1970s.

Which countries in the world have this system now?

Europe, the US, and countries like Australia and New Zealand are top of the mind for Indians, but there are some 70 countries around the world that reset clocks in the spring and the autumn.

In the US, it is practised everywhere except in Hawaii and most of Arizona. In Australia, DST is observed in New South Wales, Victoria, South Australia, and Tasmania besides some other, smaller territories; and not observed in Queensland and Western Australia among other territories.

Countries around the equator (in Africa, South America, and southeast Asia) do not usually follow DST; there isn’t much variation in the daylight they receive round the year in any case.

India does not have a DST, even though there are large parts of the country where winter days are shorter. (There is also a separate debate around the logic of sticking with only one time zone in a country as large as India.)

Most Muslim countries do not use DST — during the holy month of Ramzan, this could mean delaying the breaking of the fast for longer. Morocco has DST, but suspends it during Ramzan. However, Iran has DST, and stays with it even during Ramzan.
Countries in East Asia and Africa mostly do not have a system of DST.

Is everyone happy with this changing of clocks twice a year?

No, they are not. In fact, the European Parliament has voted to scrap DST, and starting 2021, the member states of the EU will choose between having a “permanent summertime” or “permanent wintertime”. Those who choose the former will reset their clocks for the last time in March 2021; those who choose the latter would do so in October 2021.

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

In the US, the changing of clocks is the subject of a debate that recurs every year, and a large number of people protest against the “torture”.

But what exactly is the problem with DST?

The basic idea of DST is under challenge from the way modern societies work. There are grave doubts that DST actually saves much energy.

The rationale behind setting clocks ahead of standard time during springtime was to ensure that clocks showed a later sunrise and a later sunset — in effect, a longer evening daytime. Individuals were expected to wake up an hour earlier than usual, and complete their daily work routines an hour earlier. There would be an extra hour of daylight at the end of the working day, and translate into a lower consumption of energy.

However, while more daylight did mean less use of artificial light a century ago when DST was introduced, modern societies use so much energy-consuming appliances all day long that the amount of energy saved is actually negligible.

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.

Other studies found a higher rate of workplace injuries after the switch, leading to loss 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.