Holocene calendar

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The Holocene calendar, also known as the Holocene Era or Human Era (HE), is a year numbering system that adds exactly 10,000 years to the currently dominant (AD/BC or CE/BCE) numbering scheme, placing its first year near the beginning of the Holocene geological epoch and the Neolithic Revolution, when humans shifted from a hunter-gatherer lifestyle to agriculture and fixed settlements. The current year by the Gregorian calendar, AD 2024, is 12024 HE in the Holocene calendar. The HE scheme was first proposed by Cesare Emiliani in 1993 (11993 HE), [1] though similar proposals to start a new calendar at the same date had been put forward decades earlier. [2] [3]



Cesare Emiliani's proposal for a calendar reform sought to solve a number of alleged problems with the current Anno Domini era, also called the Common Era, which number the years of the commonly accepted world calendar. These issues include:

Instead, HE uses the "beginning of human era" as its epoch, arbitrarily defined as 10,000 BC and denoted year 1 HE, so that AD 1 matches 10,001 HE. [1] 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. Emiliani later proposed that the start of the Holocene should be fixed at the same date as the beginning of his proposed era. [5]


Human Era proponents claim that it makes for easier geological, archaeological, dendrochronological, anthropological 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.


When Emiliani discussed the calendar in a follow-up article in 1994, he mentioned that there was no agreement on the date of the start of the Holocene epoch, with estimates at the time ranging between 12,700 and 10,970 years BP. [5] Since then, scientists have improved their understanding of the Holocene on the evidence of ice cores and can now more accurately date its beginning. A consensus view was formally adopted by the IUGS in 2013, placing its start at 11,700 years before 2000 (9701 BC), about 300 years more recent than the epoch of the Holocene calendar. [6]

Equivalent proposals

In 1924 Gabriel Deville proposed the use of Calendrier nouveau de chronologie ancienne (CNCA), which would start 10,000 years before AD 1, which is identical to Emiliani's much later proposal. [2]

In 1963 E.R. Hope proposed the use of Anterior Epoch (AE), which also begins at the same point. [3]


Conversion from Julian or Gregorian calendar years to the Human Era can be achieved by adding 10,000 to the AD/CE year. The present year, 2024, can be transformed into a Holocene year by adding the digit "1" before it, making it 12,024 HE. Years BC/BCE are converted by subtracting the BC/BCE year number from 10,001.

Calendar epochs and milestones in the Holocene calendar
Gregorian year ISO 8601 Holocene yearEvent
10002 BC-10001-1 HE
10001 BC-100000 HE
10000 BC-9999 [lower-alpha 1] 1 HEBeginning of the Holocene Era
9701 BC-9700300 HEEnd of the Pleistocene and beginning of the Holocene epoch [6]
4714 BC-47135287 HE Epoch of the Julian day system: Julian day 0 starts at Greenwich noon on January 1, 4713 BC of the proleptic Julian calendar, which is November 24, 4714 BC in the proleptic Gregorian calendar [7] :10
3761 BC-37606240 HEBeginning of the Anno Mundi calendar era in the Hebrew calendar [7] :11
3102 BC-31016899 HEBeginning of the Kali Yuga in Hindu cosmology [8]
2250 BC-22497751 HEBeginning of the Meghalayan age, the current and latest of the three stages in the Holocene epoch. [9] [10]
45 BC-00449956 HEIntroduction of the Julian calendar
1 BC000010000 HE Year zero at ISO 8601
1 AD000110001 HEBeginning of the Common Era and Anno Domini , from the estimate by Dionysius of the Incarnation of Jesus
622062210622 HEMigration of Muhammad from Mecca to Medina (Hijrah), starting the Islamic calendar [11] [12] at 1 AH
1582158211582 HEIntroduction of the Gregorian calendar [7] :47
1912191211912 HE Epoch of the Juche [13] and Minguo calendars [14]
1950195011950 HE Epoch of the Before Present dating scheme [15] :190
1960196011960 HE UTC Epoch
1970197011970 HE Unix Epoch [16]
1993199311993 HEPublication of the Holocene calendar
2024202412024 HECurrent year
10000+1000020000 HE
  1. Emiliani [1] states his proposal would set "the beginning of the human era at 10,000 BC" but does not mention the Julian or Gregorian calendar.

See also

Related Research Articles

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<i>Ab urbe condita</i> Ancient Roman calendar era

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Common Era (CE) and Before the Common Era (BCE) are year notations for the Gregorian calendar, the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the original Anno Domini (AD) and Before Christ (BC) notations used for the same calendar era. The two notation systems are numerically equivalent: "2024 CE" and "AD 2024" each describe the current year; "400 BCE" and "400 BC" are the same year.

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  2. 1 2 Naudin, Claude (2001). De temps en temps: Histoires de calendrier[From time to time: Calendar stories]. Le Grand Livre du Mois. ISBN   2-7028-4735-8.
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Further reading