Editing Daylight saving time (section)

==Rationale==
[[File:Clepsydra-Diagram-Fancy.jpeg|thumb|upright|alt=A water clock. A small human figurine holds a pointer to a cylinder marked by the hours. The cylinder is connected by gears to a water wheel driven by water that also floats, a part that supports the figurine.|
An ancient [[water clock]] that lets hour lengths vary with season]]

[[Industrial society|Industrialized societies]] usually follow a clock-based schedule for daily activities that do not change throughout the course of the year. The time of day that individuals begin and end work or school, and the coordination of [[Public transport|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<ref name="Minnesota">{{cite news |title= Daylight savings time |url= http://www.house.leg.state.mn.us/hinfo/swkly/1995-96/select/time.txt |work= Session Weekly |publisher= Minnesota House Public Information Office |year= 1991 |access-date= 7 August 2013 |archive-date= 16 June 2016 |archive-url= https://web.archive.org/web/20160616230715/http://www.house.leg.state.mn.us/hinfo/swkly/1995-96/select/time.txt |url-status= live }}</ref><ref name="RoSPA">{{cite web |title= Single/Double Summer Time policy paper |date= October 2006 |publisher= Royal Society for the Prevention of Accidents |archive-url= https://web.archive.org/web/20120913125519/http://www.rospa.com/RoadSafety/info/summertime_paper2006v2.pdf|archive-date=13 September 2012 |url= http://www.rospa.com/roadsafety/info/summertime_paper2006v2.pdf}}</ref> and by [[solar time]], which change [[season]]ally because of the Earth's [[axial tilt]]. North and south of the [[tropics]], daylight lasts longer in that hemisphere's summer and is shorter in that hemisphere's [[winter]], with the effect becoming greater the farther one moves away from the [[equator]]. DST is of little use for locations near the Equator, because these regions see only a small variation in daylight over the course of the year.

After synchronously resetting all clocks in a region to one hour ahead of standard time in spring in anticipation of longer daylight hours, individuals following a clock-based schedule will be awakened an hour earlier in the solar day than they would have otherwise. They will begin and complete daily work routines an hour earlier; in most cases, they will have an extra hour of daylight available to them after their workday activities.<ref name="Hudson_1895_p734">{{cite journal |author= G. V. Hudson |title= On seasonal time-adjustment in countries south of lat. 30° |journal= Transactions and Proceedings of the New Zealand Institute |year= 1895 |volume= 28 |page= 734 |url= http://rsnz.natlib.govt.nz/volume/rsnz_28/rsnz_28_00_006110.html |access-date= 3 April 2009 |archive-date= 30 March 2019 |archive-url= https://web.archive.org/web/20190330083629/http://rsnz.natlib.govt.nz/volume/rsnz_28/rsnz_28_00_006110.html |url-status= live }}</ref>{{sfnp|''Seize the Daylight''|2005|pp=115–118}}

The clock shift is partly motivated by practicality. At the summer solstice, in American temperate latitudes, for example, the sun rises around 04:30 standard time and sets around 19:30. Since most people are asleep at 04:30, it is seen as practical to treat 04:30 as if it were 05:30, thereby allowing people to wake closer to the sunrise and be active in the evening light, as the sun under DST sets an hour later (20:30). The longer evening daylight hours are attractive to golfers, for example, while farmers traditionally expressed dislike for having to be out working while [[dew]] is still heavy.

Proponents of daylight saving time argue that most people prefer more daylight hours after the typical "[[Working time#Workweek structure|nine to five]]" workday.<ref>{{cite web|url= http://www.snopes.com/science/daylight.asp|last= Mikkelson|first= David|title= Daylight Saving Time|website= Snopes|date= 13 March 2016|access-date= 17 October 2016}}</ref><ref name="Willett100">{{cite web |title= 100 years of British Summer Time |url= http://www.nmm.ac.uk/explore/astronomy-and-time/time-facts/british-summer-time/ |year= 2008 |publisher= National Maritime Museum |url-status=dead |archive-url= https://web.archive.org/web/20141228021630/http://www.nmm.ac.uk/explore/astronomy-and-time/time-facts/british-summer-time |archive-date= 28 December 2014}}</ref> 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.<ref name="Yuhas 2024 x931">{{cite web | last=Yuhas | first=Alan | title=When Is Daylight Saving Time? | website=The New York Times | date=March 6, 2024 | url=https://www.nytimes.com/article/daylight-saving-time-questions.html |quote="One of the oldest arguments for daylight saving time is that it can save energy costs. There have been many conflicting studies about whether actually it does."| access-date=March 20, 2024}}</ref><ref name="Visé 2023 g495">{{cite web | last=Visé | first=Daniel de | title=Is Daylight saving time a scam? Time, money may not be saved | website=USA TODAY | date=November 3, 2023 | url=https://www.usatoday.com/story/money/2023/11/03/daylight-saving-time-money-time-not-saved/71419089007/ |quote=" ... researchers announced that the nation had reduced its energy consumption by an annual rate of 0.03%. The meager savings came in reduced electricity consumption in the evenings during the extra days of daylight time. Other research, however, has suggested the reverse: The semiannual time shift exacts a cost, and daylight time nets little or no savings." | access-date=March 20, 2024}}</ref> For evaluation, it is required to go beyond considering only energy demand for lighting and also consider the energy used for heating or cooling buildings.<ref>{{citation|author=Eggimann Sven, Robin Mutschler, Kristina Orehounig, Massimo Fiorentini |date=2023 |doi=10.1088/1748-9326/acb0e3 |issn=1748-9326 |issue=2 |periodical=Environmental Research Letters |title=Climate change shifts the trade-off between lower cooling and higher heating demand from daylight saving time in office buildings |volume=18|page=024001 |bibcode=2023ERL....18b4001E }}<!-- auto-translated from German by Module:CS1 translator --></ref>

===Variation within a time zone===
The effect of daylight saving time also varies according to how far east or west the location is within its [[time zone]], with locations farther east inside the time zone benefiting more from DST than locations farther west in the same time zone.<ref>{{Cite news|url=https://www.washingtonpost.com/news/wonk/wp/2016/03/11/why-daylight-saving-time-isnt-as-terrible-as-people-think/|title=Why daylight saving time isn't as terrible as people think|last=Swanson|first=Anna|date=11 March 2016|newspaper=The Washington Post|access-date=27 March 2018|archive-date=11 March 2018|archive-url=https://web.archive.org/web/20180311200341/https://www.washingtonpost.com/news/wonk/wp/2016/03/11/why-daylight-saving-time-isnt-as-terrible-as-people-think/|url-status=live}}</ref> Despite a width spanning thousands of kilometers, all of China is located within a single time zone per government mandate, increasing the daylight shift the farther west one is.