Archaeologists use the term BP to mean "years Before the Present", which avoids the whole philosophical debate about AD and BC versus CE and BCE. The only trouble is, the Present, of course, changes every year. Since the BP designation was at least originally associated with radiocarbon dating, archaeologists chose the year 1950 as 'the present'. Radiocarbon dating was invented in the late 1940s, and, also, atmospheric nuclear testing was begun in the 1940s, which makes, at least the theory goes, radiocarbon dates after 1950 virtually useless, anyway.
See the entries on RCYBP and Radiocarbon Dating for further information about carbon 14 dating.
Other Common Calendar Designations
This glossary entry is part of the Dictionary of Archaeology. Any mistakes are the responsibility of Kris Hirst.
