About the idea

Local Daylight Time (LDT) is a smart clock that knows what time it should be. The LDT smart clock adjusts for the position of the sun at every location and date. Conventional clocks use the Standard Time system created by railroads in 1847 and then endlessly redefined by governments around the world. The result is a hodgepodge of arbitrary boundaries and clock changes based on an artificial sun.

Local Daylight Time has no time zone boundaries, and it ends the hassle and jet lag of changing clocks twice a year. Local Daylight Time varies continuously with location and changes gradually, never jumping to the next hour. As the seasons change, small automatic adjustments of up to one minute per day reduce sunrise variation year round, extending summer evening daylight without the disruption of Daylight Saving Time changes.

Local Daylight Time is ideal for local purposes, such as getting up and going to work. The consistent sunrise time keeps circadian rhythms natural and undisturbed, with proven health benefits. LDT works in harmony with Universal Coordinated Time (UTC) which is well suited for global time over large distances. UTC works for international conference calls, satellite broadcast times and airline schedules, while Local Daylight Time keeps communities perfectly synchronized with the sun, every day, every where.

Local Daylight Time varies with the date, like the sun. Change the date here to see this effect. Latitude (north or south of the equator) also affects Local Daylight Time. The length of the day changes with latitude, from constant at the equator to extremes of midnight sun near the poles. Local Daylight Time shifts smoothly, adjusting sunrise time proportionally and adding evening daylight hours without over extending. At extreme latitudes LDT follows mean solar time, so clocks track the sun even when it does not rise or set.

© Copyright Keith Thomas 2013