radiocarbonyears

Radiocarbon years, also known as radiocarbon years BP or years BP, are a unit of time used in radiocarbon dating. This unit is derived from the radiocarbon dating method, which measures the decay of the radioactive isotope carbon-14 (14C) in organic materials. The "BP" stands for "Before Present," where "Present" is conventionally defined as the year 1950 AD. Therefore, a radiocarbon age of 1000 BP indicates a time 1000 years prior to 1950.

The calibration of radiocarbon years into calendar years is a crucial step because the rate of 14C production in the atmosphere has not been constant throughout history. Fluctuations in cosmic ray intensity and Earth's magnetic field affect this production rate. Consequently, a raw radiocarbon age requires calibration against known-age materials, such as tree rings (dendrochronology), ice cores, or varved lake sediments. This calibration process results in a calendar age range, often expressed with a certain probability.

It is important to distinguish between radiocarbon years and calendar years. While radiocarbon years provide a direct measure based on radioactive decay, calendar years represent the actual passage of time as measured by astronomical cycles. When discussing dates derived from radiocarbon dating, specifying whether the age is calibrated or uncalibrated, and whether it is in radiocarbon years or calendar years, is essential for accuracy and clarity in scientific communication.