Why Do Clocks Change Around The World?

Daylight saving time (DST) is the period between spring and autumn when some countries adjust their clocks to make the day seem longer. Also known as daylight time, it is the practice of advancing clocks during summer months so that evening light lasts longer.

For daylight saving time, clocks are generally moved back an hour during autumn. The opposite happens in spring, when clocks are moved forward.

This practice began almost 200 years ago, but it was not until the First World War that the idea began to be taken seriously. According to The Guardian, the idea was introduced to save energy by prolonging evening daylight in summer.

Today, for countries part of the European Union, clocks go back on the last Sunday of October. New Zealand moves its clocks forward in September, while the US does it on the first Sunday of November. In much of Asia and South America, however, DST was adopted and later abandoned.

Adopting DST, however, is a contentious issue. Critics say that adopting DST does not really save energy and causes disruptions to sleep patterns or circadian rhythms, leading to health problems. Studies have even found that the risk of having a heart attack increases in the first three weekdays after switching to DST in the spring, and setting clocks back in autumn might increase road accidents.

 This year, the European Parliament voted to scrap DST by 2021, which means EU member states will choose between "permanent summertime" or "permanent wintertime".