Holocene calendar

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The Holocene calendar, popular term for the Holocene Era count or Human Era count, uses a dating system similar to astronomical year numbering but adds 10,000, placing a zero at the start of the Human Era (HE, the beginning of human civilization) the approximation of the Holocene Epoch (HE, post Ice Age) for easier geological, archaeological, dendrochronological and historical dating. The current Gregorian year can be transformed by simply placing a 1 before it (ie: 12009). The Human Era proposal was first made by Cesare Emiliani in 1993 (11993 HE). [1] [2]


[edit] Western motivation

Cesare Emiliani's proposal for a calendar reform sought to solve a number of problems with the current Gregorian Calendar, which currently serves as the commonly accepted world calendar. The issues include:

  • The Gregorian Calendar starts at the presumed year of the birth of Jesus Christ. This Christian aspect of the Gregorian calendar (especially the use of Before Christ and Anno Domini) can be offensive to non-Christian people. [3]
  • Biblical scholarship is virtually unanimous that the birth of Jesus Christ would actually have been a few years prior to AD 1. This makes the calendar inaccurate insofar as Christian dates are concerned.
  • There is no year zero as 1 BC is followed immediately by AD 1.
  • BC years are counted down when moving from past to future, thus 44 BC is after 250 BC. This makes calculating date ranges in the Holocene era across the BC/AD boundary more complicated than in the HE.

Instead, HE sets the start, the epoch, of the current era to 10,000 BC. This is a first 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 entirely within this time. All key dates in human history can then be listed using a simple increasing date scale with smaller dates always occurring before larger dates.

[edit] Gregorian conversion

Conversion to Holocene from Gregorian AD dates can be achieved by adding 10,000. BC dates are converted by subtracting the BC year from 10,001.

A useful validity check is that the last digit of BC and HE equivalents must add up to 1 or 11.

Events Gregorian years Holocene Era
Human Era
End of the Paleolithic Period,
All continents (apart from Antarctica) inhabited,
Agriculture and the domestication of animals begins,
Alteration in the Earth's magnetic field occurs,
Possible extinction of last of humanity's hominan relatives
c. 10000 BC c. 0 HE
Earliest walled city (Jericho) c. 9000 BC c. 1000 HE
First copper found in Middle East - beginning of Copper Age c. 6000 BC c. 4000 HE
Possible creation of the Egyptian calendar 4242 BC 5759 HE
Beginning of Indus Valley Civilization c. 3000 BC c. 7000 HE
Probable date of the completion of the first Egyptian pyramid 2611 BC 7390 HE
Beginning of Xia Dynasty in China c. 2100 BC c. 7900 HE
Foundation of Rome 753 BC 9248 HE
First Central American writing systems c. 400 BC c. 9600 HE
Empire of Asoka 273 BC 9728 HE
Imperial China, Qin dynasty 221 BC 9780 HE
Last year of BC era 1 BC 10000 HE
First year of Anno Domini era AD 1 10001 HE
Migration Period begins, leading to the Fall of Rome AD 300/476 10300/10476 HE
Turkic migrations begin c. AD 500 c. 10500 HE
Muslim conquests begin AD 632 10632 HE
Great Zimbabwe built c. AD 1000 c. 11000 HE
Hindu-Arabic numerals introduced to Europe AD 1202 11202 HE
Black Death decimates Asia and Europe AD 1340s 11340s HE
European expansion and colonization begins AD 1419 11419 HE
Fall of the Inca Empire AD 1572 11572 HE
Second Industrial Revolution c. AD 1850 c. 11850 HE
Second World War and nuclear fission AD 1939-1945 11939-11945 HE
First human in space AD 1961 11961 HE
Current year AD 2009 12009 HE
Last year of the current millennium AD 3000 13000 HE

[edit] References

  • David Ewing Duncan (1999). The Calendar. pp. 331–332. ISBN 1-85702-979-8. 
  • Cesare Emiliani (1993). Calendar reform. Nature. pp. 366:716. 
  • Duncan Steel (2000). Marking Time: The Epic Quest to Invent the Perfect Calendar. pp. 149–151. 
  • Günther A. Wagner (1998). Age Determination of Young Rocks and Artifacts: Physical and Chemical Clocks in Quaternary Geology and Archeology. Springer. p. 48. 
  • Timeline of World History
  • "News and comment", Geology Today, 20/3 (2004) 89–96.

[edit] See also

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