Since the second Sunday in March, most people living in the United States have been able to take advantage of an extra hour of daylight in the afternoons. That extra hour moves to the morning, starting at 2 a.m. Sunday, Nov. 4.
Most people set their clocks back an hour before going to bed Saturday night. Unlike when time springs forward in March, the end of daylight-saving time allows for an extra hour of sleep.
Twice a year, the start and end of the time change, a debate is triggered on the advantages and disadvantages of DST. Benefits include more time during warm-weather months for activities after work, including shopping, which some say boosts retailers’ potential for making more sales. The negatives revolve around disruption of sleep cycles and activities tied to the actual rising and setting of the sun.
Benjamin Franklin is credited by most for coming up with the idea of DST as a way to save energy by reducing the need for electricity to light homes during the evening hours. The United States first used DST during World War I, and in 1918, a federal law was passed establishing start and end times for DST. The practice was voluntary and states could choose to participate or not.
During World War II, DST became mandatory as resources became scarce and the need to conserve energy became critical. From Feb. 9, 1942 to Sept. 30, 1945, DST was in place year-round. At the end of World War II, DST continued, but was again left up to the states to decide to use it or not.
In 1966, Congress passed the first Uniform Time Act that said clocks should move ahead on the last Sunday in April and then set back an hour the last Sunday in October. During the Arab oil embargo in 1973-1974, the U.S. again left DST in effect through the winter months to save energy.
In 1986, the Uniform Time Act was amended and the time change moved to the first Sunday in April with the end of DST remaining unchanged, the last Sunday in October. Since 2007, federal law calls for DST to begin the second Sunday in March and to end on the first Sunday in November. However, states can opt out and some do, including Arizona and Hawaii. About 70 countries participate in DST.
The debate as to whether DST does save energy in today’s world continues with federal studies dating back to 2008 saying it does help lessen the demand for electricity and related resources. Some point to an added bonus tied to an increase in outdoors activities much in need by a country struggling to control a growing trend of obesity.
Still others argue that the human body is wired to adjust to light and dark cycles, which are disrupted by a twice-a-year change in time, resulting in a loss in productivity due to people being tired and sluggish as their bodies struggle to adjust. Some say the practice is unhealthy with studies showing an increase in heart attacks and other life-threatening medical conditions.
However, studies on preference continue to show that people generally enjoy that extra hour of daylight that comes in the spring and the promise of warmer weather. During the winter months, the weather usually forces most people inside, so DST makes no difference, researchers say.
Most electronic clocks will roll back an hour automatically, but not all, so be sure to check the time when you wake up to avoid confusion. Local firefighters also advise residents to use the time change as an opportunity to check and if needed, replace batteries in smoke alarms.