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 shifted from a hunter-gatherer lifestyle to agriculture and fixed settlements. The current year by the Gregorian calendar, AD 2025, is 12025 HE in the Holocene calendar. The HE scheme was first proposed by Cesare Emiliani in 1993 (11993 HE), though similar proposals to start a new calendar at the same date had been put forward decades earlier. Emiliani thereby dismissed his original proposal to align the era with the 7980-year Julian cycles, i.e. start with the epoch in 4713 BCE (5288 HE).

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 numbers 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. 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.

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. 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.

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.

Since 1929, Dievturība adherents use Latviskā ēra (the Latvian Era) which begins at the same point; this coincides with the first inhabitants’ influx to the territory of present Latvia (10500–10047 BCE). According to the Latvian Era, 12025 is written for 2025 CE. Detailed explanation of Latvian Era by Ernests Brastiņš was first published in 1934.

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