Daylight saving time

Why do we "fall back?"

Don’t forget to change your clocks! Daylight saving time ends in 2022 for most of the United States on Sunday, November 6.

The law says that people must set their clocks back to standard time at 2 a.m. on the first Sunday in November. That means changing the clock back one hour at 2 a.m. During the winter months, there will be a bit more light in the morning, but the sun will set earlier in the evening.

Some places, like American Samoa, Hawaii, and most of Arizona, don't mess with Father Time. But why do we move our clocks one hour forward in the spring anyway? There was no standardized time until train travel became common. The U.S. railroad industry established time zones with standard times in 1883, and Congress made the railroad's system a law in 1918. The next year, the decision of whether or not to observe daylight saving time was left up to individual jurisdictions.

When updating legislation in the 1980s, Congress noted that daylight saving time has many benefits, including "more daylight outdoor playtime for the children and youth of our Nation."

Not everyone agrees that this is beneficial, however. Till Roenneberg, a chronobiologist at Ludwig-Maximillians-University in Munich, Germany, says that our bodies never really adjust to the different light schedule during daylight saving time.

Learn more about daylight savings time at National Geographic.