Links to Time Related Information Sources

A useful collection of knowledge related to the subject of time. Taken for granted by most, time is a deep and interesting subject that affects everyone. Read! Learn! Enjoy!

Time Keeping

Time standards - How is time measured.
Universal Time - time standards based on the rotation of the Earth.
Coordinated Universal Time - the primary world standard for clocks and time.
Time Zones - carving up universal time.
Nautical time - carving up the oceans.
Earth's rotation - the variable constant of UTC.
Swatch Internet Time - a great idea?
Decimal Time - can't we get rid of sexagesimal?
Sexagesimal - really?
Convert time to decimal - calculator.
Metric Time? A consideration of possibilities.
Metric time - just a way to measure time, not for time of day.
Solar Time - Apparent and mean. Sundials and fictitious suns.
Astronomical Information - From the US Naval Observatory.
Time and Date - a good site for information and tools
Why is Singapore in the “Wrong” Time Zone?
Network Time Protocol
Original Time Zone Proposal "Uniform Non-Local Time - Terrestrial Time" (PDF)
How much is time wrong around the world?

Daylight Saving

Daylight Saving - Wikipedia's take
Book - Seize the Daylight: The Curious and Contentious Story of Daylight Saving Time
Spring Forward: The Annual Madness of Daylight Saving Time
Transition to daylight saving time reduces sleep duration plus sleep efficiency of the deprived sleep.
The human circadian clock's seasonal adjustment is disrupted by daylight saving time.
How did they decide when and by how much to make the “daylight savings time” adjustment?
The dates of daylight savings time do not come close to minimizing variance in sunrise.
Daylight Saving web site, lot's of history
First proposal for daylight saving time
DST Saves lives.
Shifts to and from Daylight Saving Time and Incidence of Myocardial Infarction
Transitions into and out of daylight saving time compromise sleep and the rest-activity cycles
Spring and Autumn daylight saving time changes: Studies of adjustment in sleep timings, mood, and efficiency
Daylight Saving Time links
The Case Against Daylight Saving Time
Daylight Saving Time Is America's Greatest Shame

Circadian rhythm

Circadian rhythm
Light effects on circadian rhythm
Average sunrise time predicts depression prevalence.
The human circadian clock's seasonal adjustment is disrupted by daylight saving time.
Light Pollution and Sleep - Steven Lockley (Harvard Medical School)
EUCLOCK - Entrainment of the Circadian Clock
Photosensitive ganglion cell
Circadian Rhythm and Human Health
The human circadian clock entrains to sun time
To Keep Teenagers Alert, Schools Let Them Sleep In
Daylight saving time linked to heart attacks: study


Sunrise Equation
Solar Time
Sun or Moon Rise/Set Table for One Year
Fourier Sunrise calculation
Physics sunrise calculation
Effect of altitude on sunrise
The Equation of Time (PDF)
The Equation of Time
The Analemma
Position of the Sun
NOAA Excel Solar calculators
NOAA Web Solar Calculator (Javascript)

Time Zone Maps and data

Eric Mueller's time zone maps
CIA Time Zone Map
Natural Earth's shape file from the CIA time zone map
NOAA Elevation data
KML Map Creator
KML Editor
Calculate distance, bearing and more between Latitude/Longitude points
Python shape file to KML
Time Zones of the United States
IANA Time Zone Database
Sources for Time Zone and Daylight Saving Time Data
Date and Time Gateway - Timezone Selector
List of tz database time zones
KML Reference
pyKML Python package for KML
Python TZ database
Google Maps API Tutorial
Mapping tools and calculators
GIS Stack Exchange
World Sunlight Map

© Copyright Keith Thomas 2013