Local time in GUAM - UNITED STATES
Guam - United States Actual Time and Date
Synchronized clock on atomic clock in real time
Current time & Weather at Guam
Current Local time
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Guam timezone information
Geographical and astronomical datas : United States
Time information on United States - Guam
Clock shifts affecting apparent sunrise and sunset times at Greenwich in 2007.
DST has mixed effects on health
In societies with fixed work schedules it provides more afternoon sunlight for outdoor exercise.
Sunlight strongly influences seasonal affective disorder
DST may help in depression by causing individuals to rise earlier, The Retinitis Pigmentosa Foundation Fighting Blindness, chaired by blind sports magnate Gordon Gund, successfully lobbied in 1985 and 2005 for U.S. DST extensions, Clock shifts disrupt sleep and reduce its efficiency.
DST's clock shifts have the obvious disadvantage of complexity
People must remember to change their clocks; this consumes time, particularly for mechanical clocks that cannot be moved backward safely.
People who work across time zone boundaries need to keep track of multiple DST rules, as not all locations observe DST or observe it the same way
The length of the calendar day becomes variable; it is no longer always 24 hours
Disruption to meetings, travel, broadcasts, billing systems, and records management is common, and can be expensive.
A standing stone in a grassy field surrounded by trees
The stone contains a vertical sundial centered on 1 o'clock, and is inscribed "HORAS NON NUMERO NISI ÆSTIVAS" and "SUMMER TIME ACT 1925".
The William Willett Memorial Sundial is always on DST.
Some computer-based systems require downtime or restarting when clocks shift; ignoring this requirement damaged a German steel facility in 1993.
These problems are compounded when the DST rules themselves change; software developers must test and perhaps modify many programs, and users must install updates and restart applications
Consumers must update devices such as programmable thermostats with the correct DST rules, or manually adjust the devices' clocks.
Some clock-shift problems could be avoided by adjusting clocks continuously or at least more gradually—for example, Willett at first suggested weekly 20-minute transitions—but this would add complexity and has never been implemented.
DST inherits and can magnify the disadvantages of standard time
For example, when reading a sundial, one must compensate for it along with time zone and natural discrepancies.
Daylight saving has caused controversy since it began.