Daylight Savings Time Ends

Taken from Wikipedia

Daylight saving time

From Wikipedia, the free encyclopedia

This article is about the concept of daylight saving time. For local implementations, see Daylight saving time by country.

Daylight saving time (DST) or summer time is the practice of advancing clocks during summer months by one hour so that in the evening hours day light is experienced later, while sacrificing normal sunrise times. Typically, users in regions with summer time adjust clocks forward one hour close to the start of spring and adjust them backward in the autumn to standard time.^[1]

New Zealander George Hudson proposed the modern idea of daylight saving in 1895.^[2] Germany and Austria-Hungary organized the first implementation, starting on 30 April 1916. Many countries have used it at various times since then, particularly since the energy crisis of the 1970s.

The practice has received both advocacy and criticism.^[1] Putting clocks forward benefits retailing, sports, and other activities that exploit sunlight after working hours,^[3] but can cause problems for evening entertainment and for other activities tied to sunlight, such as farming.^[4][5] Although some early proponents of DST aimed to reduce evening use of incandescent lighting, which was formerly a primary use of electricity,^[6] modern heating and cooling usage patterns differ greatly and research about how DST currently affects energy use is limited or contradictory.^[7]

DST clock shifts sometimes complicate timekeeping and can disrupt travel, billing, record keeping, medical devices, heavy equipment,^[8] and sleep patterns.^[9] Computer software can often adjust clocks automatically, but policy changes by various jurisdictions of the dates and timings of DST may be confusing.^[10]

Rationale[edit]

Industrialized societies generally follow a clock-based schedule for daily activities that does not change throughout the course of the year. The time of day that individuals begin and end work or school, and the coordination of mass transit, for example, usually remain constant year-round. In contrast, an agrarian society's daily routines for work and personal conduct are more likely governed by the length of daylight hours^[11][12] and solar time, which change seasonally because of the Earth's axial tilt. North and south of the tropics daylight lasts longer in summer and shorter in winter, the effect becoming greater as one moves away from the tropics.

By synchronously resetting all clocks in a region to one hour ahead of Standard Time (one hour "fast"), individuals who follow such a year-round schedule will wake an hour earlier than they would have otherwise; they will begin and complete daily work routines an hour earlier, and they will have an extra hour of daylight after their workday activities.^[13][14] However, they will have one less hour of daylight at the start of each day, making the policy less practical during winter.^[15][16]

While the times of sunrise and sunset change at roughly equal rates as the seasons change, proponents of Daylight Saving Time argue that most people prefer a greater increase in daylight hours after the typical "nine-to-five" workday.^[17][18] Supporters have also argued that DST decreases energy consumption by reducing the need for lighting and heating, but the actual effect on overall energy use is heavily disputed. (See: Dispute over benefits and drawbacks section)

The manipulation of time at higher latitudes (for example Iceland, Nunavut or Alaska) has little impact on daily life, because the length of day and night changes more extremely throughout the seasons (in comparison to other latitudes), and thus sunrise and sunset times are significantly out of sync with standard working hours regardless of manipulations of the clock.^[19] DST is also of little use for locations near the equator, because these regions see only a small variation in daylight throughout the year.^[20]

History[edit]

Ancient water clock that lets hour lengths vary with season.

Although they did not fix their schedules to the clock in the modern sense, ancient civilizations adjusted daily schedules to the sun more flexibly than modern DST does, often dividing daylight into twelve.... to continue, click here.

Until next time!
Cherise, the Mompreneur