Holocene calendar

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 transitioned from a hunter-gatherer lifestyle to agriculture and fixed settlements. The year 2019 in the Holocene calendar is 12,019 HE. The HE scheme was first proposed by Cesare Emiliani in 1993.[1]


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 the erroneous estimation of the birth year of Jesus. The era places Jesus's birth year in AD 1, but modern scholars have determined that he was likely born in or before 4 BC. Emiliani argued that replacing it with the approximate beginning of the Holocene makes more sense.
  • The birth date of Jesus is a less universally relevant epoch event than the approximate beginning of the Holocene.
  • The years BC/BCE are counted down when moving from past to future, making calculation of time spans difficult.
  • The Anno Domini era has no year zero, with 1 BC followed immediately by AD 1, complicating the calculation of timespans further. This is equally true of the Common Era, its non-religious equivalent.

Instead, HE uses the "beginning of human era" as its epoch, arbitrarily defined as 10,000 BC 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 would later propose that the start of the Holocene be fixed at the same date as the beginning of his proposed era.[2]


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.


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.[2] 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.[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, 2019, can be transformed into a Holocene year by adding the digit "1" before it, making it 12,019 HE. Years BC/BCE are converted by subtracting the BC/BCE year number from 10,001.

Comparison of some historic dates in the Gregorian and the Holocene calendar
Gregorian year ISO 8601 Holocene year Event
10001 BC −10000[a] 0 HE Beginning of the Holocene Era
9701 BC −9700 300 HE End of the Pleistocene and beginning of the Holocene epoch[3]
4714 BC −4713 5287 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[4]:10
3761 BC −3760 6240 HE Beginning of the Anno Mundi era in the Hebrew calendar[4]:11
3102 BC −3101 6899 HE Beginning of the Kali Yuga era in Hindu cosmology
2250 BC −2251 7751 HE Beginning of the Meghalayan age, the current and latest of the three stages in the holocene era. [5][6]
45 BC −0044 9956 HE Introduction of the Julian calendar
1 BC +0000 10000 HE Year zero at ISO 8601
AD 1 +0001 10001 HE Beginning of the Common Era (Anno Domini), from the (incorrect) estimate by Dionysius of the Incarnation of Jesus
622, 1 AH +0622 10622 HE Migration of Muhammad from Mecca to Medina (Hegira), starting the Islamic calendar[7][8]
1582 +1582 11582 HE Introduction of the Gregorian calendar[4]:47
1912 +1912 11912 HE Epoch of the Juche and Minguo calendars
1950 +1950 11950 HE Epoch of the Before Present dating scheme[9]:190
1970 +1970 11970 HE Unix Epoch[10]
1993 +1993 11993 HE Publication of the Holocene calendar
2019 +2019 12019 HE Current year
10000 +10000 20000 HE
  1. ^ Emiliani[1] states his proposal "would make the year AD 1 into the year 10,001" but does not mention the Julian or Gregorian calendar. The proposal does not explicitly designate any particular date as the beginning of the era.

See also


  1. ^ a b c Emiliani, Cesare (1993). "Correspondence – Calendar Reform". Nature. 366 (6457): 716. Bibcode:1993Natur.366..716E. doi:10.1038/366716b0. Setting the beginning of the human era at 10,000 BC would date […] the birth of Christ at [25 December] 10,000
  2. ^ a b Emiliani, Cesare (1994). "Calendar reform for the year 2000". Eos. 75 (19): 218. Bibcode:1994EOSTr..75..218E. doi:10.1029/94EO00895.
  3. ^ a b Walker, Mike; Jonsen, Sigfus; Rasmussen, Sune Olander; Popp, Trevor; Steffensen, Jørgen-Peder; Gibbard, Phil; Hoek, Wim; Lowe, John; Andrews, John; Björck, Svante; Cwynar, Les C.; Hughen, Konrad; Kershaw, Peter; Kromer, Bernd; Litt, Thomas; Lowe, David J.; Nakagawa, Takeshi; Newnham, Rewi; Schwander, Jacob (2009). "Formal definition and dating of the GSSP (Global Stratotype Section and Point) for the base of the Holocene using the Greenland NGRIP ice core, and selected auxiliary records" (PDF). Journal of Quaternary Science. 24 (1): 3–17. Bibcode:2009JQS....24....3W. doi:10.1002/jqs.1227. Archived (PDF) from the original on 2013-11-04.
  4. ^ a b c Dershowitz, Nachum; Reingold, Edward M. (2008). Calendrical Calculations (3rd ed.). Cambridge University Press. ISBN 978-0-521-70238-6.
  5. ^ "ICS chart containing the Quaternary and Cambrian GSSPs and new stages (v 2018/07) is now released!". Retrieved February 6, 2019.
  6. ^ Conners, Deanna (September 18, 2018). "Welcome to the Meghalayan age". Retrieved February 6, 2019.
  7. ^ Aisha El-Awady (2002-06-11). "Ramadan and the Lunar Calendar". Islamonline.net. Retrieved 2006-12-16.
  8. ^ Hakim Muhammad Said (1981). "The History of the Islamic Calendar in the Light of the Hijra". Ahlul Bayt Digital Islamic Library Project. Retrieved 2006-12-16.
  9. ^ Currie Lloyd A (2004). "The Remarkable Metrological History of Radiocarbon Dating [II]" (PDF). Journal of Research of the National Institute of Standards and Technology. 109 (2): 185–217. doi:10.6028/jres.109.013. PMC 4853109. PMID 27366605.
  10. ^ "The Open Group Base Specifications Issue 7, Rationale, section 4.16 Seconds Since the Epoch". The OpenGroup. 2018.

Further reading

External links

10th millennium BC

The 10th millennium BC spanned the years 10,000 through 9001 BC. It marks the beginning of the Mesolithic (northern and western Europe) and Epipaleolithic (Levant and Near East) periods, which together form the first part of the Holocene epoch that is generally reckoned to have begun c.9,700 BC (about 11.7ka) and is the current geological epoch. It is impossible to precisely date events that happened around the time of this millennium and all dates mentioned here are estimates mostly based on geological and anthropological analysis.

1st century BC

The 1st century BC, also known as the last century BC, started on the first day of 100 BC and ended on the last day of 1 BC. The AD/BC notation does not use a year zero; however, astronomical year numbering does use a zero, as well as a minus sign, so "2 BC" is equal to "year –1". This is the 100th century in the Holocene calendar; it spans the years 9,901 to 10,000. 1st century AD (Anno Domini) follows.

In the course of the century all the remaining independent lands surrounding the Mediterranean were steadily brought under Roman control, being ruled either directly under governors or through puppet kings appointed by Rome. The Roman state itself was plunged into civil war several times, finally resulting in the marginalization of its 500-year-old republic, and the embodiment of total state power in a single man—the emperor.

The internal turbulence that plagued Rome at this time can be seen as the death throes of the Roman Republic, as it finally gave way to the autocratic ambitions of powerful men like Sulla, Julius Caesar, Mark Antony and Octavian. Octavian's ascension to total power as the emperor Augustus is considered to mark the point in history where the Roman Republic ends and the Roman Empire begins. Some scholars refer to this event as the Roman Revolution. It is believed that the birth of Jesus, the central figure of Christianity took place at the close of this century.

In the eastern mainland, the Han Dynasty began to decline and the court of China was in chaos in the latter half of this century. Trapped in a difficult situation, the Xiongnu had to begin emigration to the west or attach themselves to the Han.

After the Development of Agriculture

After the Development of Agriculture (A.D.A.) is a system for counting years forward from 8000 BCE, making 2019 the year 10019 ADA. It was developed in feminist thealogy. It is not often used.

A.D.A. is similar to the Holocene calendar system, with which the year 2019 is written as 12019 HE.

Anno Domini

The terms anno Domini (AD) and before Christ (BC) are used to label or number years in the Julian and Gregorian calendars. The term anno Domini is Medieval Latin and means "in the year of the Lord", but is often presented using "our Lord" instead of "the Lord", taken from the full original phrase "anno Domini nostri Jesu Christi", which translates to "in the year of our Lord Jesus Christ".

This calendar era is based on the traditionally reckoned year of the conception or birth of Jesus of Nazareth, with AD counting years from the start of this epoch, and BC denoting years before the start of the era. There is no year zero in this scheme, so the year AD 1 immediately follows the year 1 BC. This dating system was devised in 525 by Dionysius Exiguus of Scythia Minor, but was not widely used until after 800.The Gregorian calendar is the most widely used calendar in the world today. For decades, it has been the unofficial global standard, adopted in the pragmatic interests of international communication, transportation, and commercial integration, and recognized by international institutions such as the United Nations.Traditionally, English followed Latin usage by placing the "AD" abbreviation before the year number. However, BC is placed after the year number (for example: AD 2019, but 68 BC), which also preserves syntactic order. The abbreviation is also widely used after the number of a century or millennium, as in "fourth century AD" or "second millennium AD" (although conservative usage formerly rejected such expressions). Because BC is the English abbreviation for Before Christ, it is sometimes incorrectly concluded that AD means After Death, i.e., after the death of Jesus. However, this would mean that the approximate 33 years commonly associated with the life of Jesus would neither be included in the BC nor the AD time scales.Terminology that is viewed by some as being more neutral and inclusive of non-Christian people is to call this the Current or Common Era (abbreviated as CE), with the preceding years referred to as Before the Common or Current Era (BCE). Astronomical year numbering and ISO 8601 avoid words or abbreviations related to Christianity, but use the same numbers for AD years.

Anno Lucis

Anno Lucis (“in the Year of Light”) is a dating system used in Masonic ceremonial or commemorative proceedings, which is equivalent to the Gregorian year plus 4000. It is similar to Anno Mundi.

Astronomical year numbering

Astronomical year numbering is based on AD/CE year numbering, but follows normal decimal integer numbering more strictly. Thus, it has a year 0; the years before that are designated with negative numbers and the years after that are designated with positive numbers. Astronomers use the Julian calendar for years before 1582, including the year 0, and the Gregorian calendar for years after 1582, as exemplified by Jacques Cassini (1740), Simon Newcomb (1898) and Fred Espenak (2007).The prefix AD and the suffixes CE, BC or BCE (Common Era, Before Christ or Before Common Era) are dropped. The year 1 BC/BCE is numbered 0, the year 2 BC is numbered −1, and in general the year n BC/BCE is numbered "−(n − 1)" (a negative number equal to 1 − n). The numbers of AD/CE years are not changed and are written with either no sign or a positive sign; thus in general n AD/CE is simply n or +n. For normal calculation a number zero is often needed, here most notably when calculating the number of years in a period that spans the epoch; the end years need only be subtracted from each other.

The system is so named due to its use in astronomy. Few other disciplines outside history deal with the time before year 1, some exceptions being dendrochronology, archaeology and geology, the latter two of which use 'years before the present'. Although the absolute numerical values of astronomical and historical years only differ by one before year 1, this difference is critical when calculating astronomical events like eclipses or planetary conjunctions to determine when historical events which mention them occurred.

Before Present

Before Present (BP) years is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred in the past. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date of the age scale, reflecting the origin of practical radiocarbon dating in the 1950s. The abbreviation "BP" has alternatively been interpreted as "Before Physics"; that is, before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, making dating after that time likely to be unreliable.In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating.


A calendar is a system of organizing days for social, religious, commercial or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single, specific day within such a system. A calendar is also a physical record (often paper) of such a system. A calendar can also mean a list of planned events, such as a court calendar or a partly or fully chronological list of documents, such as a calendar of wills.

Periods in a calendar (such as years and months) are usually, though not necessarily, synchronised with the cycle of the sun or the moon. The most common type of pre-modern calendar was the lunisolar calendar, a lunar calendar that occasionally adds one intercalary month to remain synchronised with the solar year over the long term.

The term calendar is taken from calendae, the term for the first day of the month in the Roman calendar, related to the verb calare "to call out", referring to the "calling" of the new moon when it was first seen.

Latin calendarium meant "account book, register" (as accounts were settled and debts were collected on the calends of each month). The Latin term was adopted in Old French as calendier and from there in Middle English as calender by the 13th century (the spelling calendar is early modern). A calendar can be on paper or electronic device.

Cesare Emiliani

Cesare Emiliani (8 December 1922 – 20 July 1995) was an Italian-American scientist, geologist, micropaleontologist, and the founder of paleoceanography, developing the timescale of marine isotope stages, which despite modifications remains in use today.

He established that the ice ages of the last half million years or so are a cyclic phenomenon, which gave strong support to the hypothesis of Milankovitch and revolutionized ideas about the history of the oceans and of the glaciations. He was also the proponent of Project "LOCO" (for Long Cores) to the U.S. National Science Foundation. The project was a success providing evidence of the history of the oceans and also serving to test the hypotheses of seafloor spreading and plate tectonics.

Cesare Emiliani was honored by having the genus Emiliania erected as home for the taxon huxleyi, which had previously been assigned to Coccolithus. He was further honored by receiving the Vega Medal of the Swedish Society for Anthropology and Geography (SSAG) (Swedish: Svenska Sällskapet för Antropologi och Geografi) in 1983, and the Alexander Agassiz Medal of the U.S. National Academy of Sciences in 1989 for his isotopic studies on Pleistocene and Holocene planktic foraminifera.

In his later years, he dedicated a great deal of time to promoting a calendar reform based on the Holocene calendar (HE) concept to eliminate the BC–AD chronology gap caused by the lack of a year 0.


An epoch, for the purposes of chronology and periodization, is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured.

The moment of epoch is usually decided by congruity (makes simple sense), or by following conventions understood from the epoch in question. The epoch moment or date is usually defined from a specific, clear event of change, epoch event. In a more gradual change, a deciding moment is chosen when the epoch criterion was reached.


The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years before present, after the last glacial period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch.The Holocene has seen the growth and impacts of the human species worldwide, including all its written history, development of major civilizations, and overall significant transition toward urban living in the present. Human impacts on modern-era Earth and its ecosystems may be considered of global significance for future evolution of living species, including approximately synchronous lithospheric evidence, or more recently hydrospheric and atmospheric evidence of human impacts. In July 2018, the International Union of Geological Sciences split the Holocene epoch into three distinct subsections, Greenlandian (11,700 years ago to 8,326 years ago), Northgrippian (8,326 years ago to 4,200 years ago) and Meghalayan (4,200 years ago to the present), as proposed by International Commission on Stratigraphy. The boundary stratotype of Meghalayan is a speleothem in Mawmluh cave in India, and the global auxiliary stratotype is an ice core from Mount Logan in Canada.The name Holocene comes from the Ancient Greek words ὅλος (holos, whole or entire) and καινός (kainos, new), meaning "entirely recent".

Khorat Plateau

The Khorat Plateau (Thai: ที่ราบสูงโคราช) is a plateau in the northeastern Isan region of Thailand. The plateau forms a natural region, named after the short form of Nakhon Ratchasima, a historical barrier controlling access to and from the area.

List of calendars

This is a list of calendars. Included are historical calendars as well as proposed ones. Historical calendars are often grouped into larger categories by cultural sphere or historical period; thus O'Neil (1976) distinguishes the groupings Egyptian calendars (Ancient Egypt), Babylonian calendars (Ancient Mesopotamia), Indian calendars (Hindu and Buddhist traditions of the Indian subcontinent), Chinese calendars and Mesoamerican calendars.

These are not specific calendars but series of historical calendars undergoing reforms or regional diversification.

In Classical Antiquity, the Hellenic calendars inspired the Roman calendar, including the solar Julian calendar introduced in 45 BC. Many modern calendar proposals, including the Gregorian calendar itself, are in turn modifications of the Julian calendar.

List of timelines

This is a list of timelines currently on Wikipedia.

Long Now Foundation

The Long Now Foundation, established in 1996, is an American public, non-profit organization based in San Francisco that seeks to become the seed of a very long-term cultural institution. It aims to provide a counterpoint to what it views as today's "faster/cheaper" mindset and to promote "slower/better" thinking. The Long Now Foundation hopes to "creatively foster responsibility" in the framework of the next 10,000 years. In a manner somewhat similar to the Holocene calendar, the foundation uses 5-digit dates to address the Year 10,000 problem (e.g., by writing "02019" rather than "2019"). The organisation's logo, a capital X with an overline, is a representation of 10,000 in Roman numerals.

Solar calendar

A solar calendar is a calendar whose dates indicate the season or almost equivalently the apparent position of the Sun relative to the stars. The Gregorian calendar, widely accepted as standard in the world, is an example of a solar calendar.

The main other type of calendar is a lunar calendar, whose months correspond to cycles of Moon phases. The months of the Gregorian calendar do not correspond to cycles of Moon phase.

World Calendar

The World Calendar is a proposed reform of the Gregorian calendar created by Elisabeth Achelis of Brooklyn, New York in 1930.

Year 10,000 problem

The year 10,000 problem (also known as the Y10K problem or the deca-millennium bug) is the class of all potential time formatting and storage bugs that would emerge when the need to express years with five digits arises. The problem can have discernible effects today, but is also sometimes mentioned for humorous effect as in RFC 2550.

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