The Holocene calendar, also known as the Holocene Era (HE) or Human era, is a year numbering system that adds exactly 10,000 years to the currently world-dominant Common Era Anno Domini, placing its first year near the beginning of the Holocene epoch and the Neolithic revolution. The Human Era was first proposed by the scientist Cesare Emiliani in 1993.
Cesare Emiliani's proposal for a calendar reform sought to solve a number of alleged problems with the current Anno Domini era, which number the years of the commonly accepted world calendar. These issues include:
- The Anno Domini era is based on an erroneous estimation of the birth year of Jesus. The era places Jesus' birth year in 1 BC, but modern scholars have determined that he was born in or before 4 BC. Emiliani argues that replacing it with the approximate beginning of the Holocene era makes sense.
- The birth of Jesus is a less universally relevant epoch event than the approximate beginning of the Holocene era.
- The years BC are counted down when moving from past to future, making calculation of timespans difficult.
- The Anno Domini era has no year zero, with 1 BC followed immediately by AD 1, complicating the calculation of timespans further.
Instead, HE places its epoch to 10,000 BC. This is a rough approximation of the start of the current geologic epoch, the Holocene (the name means entirely recent). The motivation for this is that human civilization (e.g. the first settlements, agriculture, etc.) is believed to have arisen within this time.
Human Era proponents claim that it makes for easier geological, archaeological, dendrochronological and historical dating, as well as that it bases its epoch on an event more universally relevant than the birth of Jesus. All key dates in human history can then be listed using a simple increasing date scale with smaller dates always occurring before larger dates. Another gain is that the Holocene Era starts before the other Calendar Eras. So it could be useful for the comparison and conversion of dates from different calendars.
Conversion from Julian or Gregorian AD years to the Human Era can be achieved by adding 10,000 to the AD year. The current year of AD 2015 can be transformed into a Holocene year by adding the digit "1" before it, making it 12015 HE. BC years are converted by subtracting the BC year from 10,001. A useful validity check is that the last single digits of BC and HE equivalent pairs must add up to 1 or 11.
|Gregorian years||ISO 8601||Human Era
|30001 BC||−30000||20000 BHE||Pleistocene|
|10001 BC||−10000||0 HE||Approximate begin of the Holocene|
|10000 BC||−9999||1 HE|
|9000 BC||−8999||1000 HE||Earliest known walled city (Jericho)|
|8000 BC||-7999||2001 HE||Start of After the Development of Agriculture (A.D.A.)|
|4713 BC||-4712||5288 HE||Start of the Julian date (JD) at January 1, Greenwich noon, Julian proleptic calendar|
|3761 BC||-3760||6240 HE||Begin of Anno Mundi in the Jewish calendar|
|2720 BC||-2719||7281 HE||Regency of Pharao Djoser, Building of the first pyramid|
|2700 BC||-2699||7301 HE|
|1000 BC||−0999||9001 HE|
|776 BC||-0775||9226 HE||Begin of the first Olympiad|
|753 BC||-0752||9248 HE||Legendary Founding of Rome, Start of ab urbe condita|
|544 BC||-0543||9457 HE||Legendary death of Siddhartha Gautama, Start of the Buddhist Era|
|100 BC||−0099||9901 HE|
|45 BC||-0044||9956 HE||Introduction of the Julian calendar|
|44 BC||-0043||9957 HE||Assassination of Julius Caesar on the Ides of March|
|2 BC||−0001||9999 HE|
|1 BC||+0000||10000 HE||Year Zero at ISO 8601|
|1 AD||+0001||10001 HE||Begin of the Vulgar Era Anno Salutis|
|2 AD||+0002||10002 HE|
|535/536 AD||+0535/+0536||10535/10536 HE||Extreme weather events of 535–536|
|622 AD||+0622||10622 HE||Migration of Muhammad from Mecca to Medina (Hijrah), Begin of the Islamic calendar|
|1492 AD||+1492||11492 HE||Voyages of Christopher Columbus|
|1502 AD||+1502||11502 HE|
|1582 AD||+1582||11582 HE||Introduction of the Gregorian calendar|
|1639 AD||+1639||11639 HE||Wars of the Three Kingdoms|
|1651 AD||+1651||11651 HE|
|1707 AD||+1707||11707 HE||Acts of Union 1707, Foundation of the Kingdom of Great Britain|
|1776 AD||+1776||11776 HE||United States Declaration of Independence|
|1775 AD||+1775||11775 HE||American Revolutionary War|
|1783 AD||+1783||11783 HE|
|1789 AD||+1789||11789 HE||Storming of the Bastille, Begin of the French Revolution|
|1800 AD||+1800||11800 HE||Foundation of the United Kingdom of Great Britain and Ireland with the Acts of Union 1800|
|1804 AD||+1804||11804 HE||Coronation of Napoleon I|
|1815 AD||+1815||11815 HE||Battle of Waterloo|
|1816 AD||+1816||11816 HE||Year Without a Summer Eighteen hundred and frozen to death|
|1861 AD||+1861||11861 HE||American Civil War|
|1865 AD||+1865||11865 HE|
|1914 AD||+1914||11914 HE||World War I|
|1918 AD||+1918||11918 HE|
|1922 AD||+1922||11922 HE||Foundation of the Irish Free State and the current United Kingdom; Independence of the Kingdom of Egypt|
|1937 AD||+1937||11937 HE||Transformation of the Irish Free State to the Republic of Ireland|
|1939 AD||+1939||11939 HE||World War II|
|1945 AD||+1945||11945 HE|
|1950 AD||+1950||11950 HE||Commencement date of Before Present|
|1962 AD||+1962||11962 HE||Cuban Missile Crisis|
|1969 AD||+1969||11969 HE||First manned Moon landing|
|1993 AD||+1993||11993 HE||Publication of the Holocene calendar by Cesare Emiliani|
|2015 AD||+2015||12015 HE||Current Year|
|10000 AD||+10000||20000 HE|
- David Ewing Duncan (1999). The Calendar. pp. 331–332. ISBN 1-85702-979-8.
- Duncan Steel (2000). Marking Time: The Epic Quest to Invent the Perfect Calendar. John Wiley and Sons. pp. 149–151. ISBN 978-0-471-29827-4.
- Günther A. Wagner (1998). Age Determination of Young Rocks and Artifacts: Physical and Chemical Clocks in Quaternary Geology and Archeology. Springer. p. 48. ISBN 978-3-540-63436-2.
- "News and comment", Geology Today, 20/3 (2004) 89–96.
- Timeline of World History
- Geologic TimeScale Foundation: GSSP Table, engineering.purdue.edu
- Comparison of some historic dates in the gregorian and the Holocene calendar
- Article about the Holocene calendar