The abbreviation "BP", with the same meaning, has also been interpreted both of which requested that publications should use the unit "a" for year and reserve the term "BP" for radiocarbon estimations. A large quantity of contemporary oxalic acid dihydrate was prepared as NBS Standard Reference Material (SRM) 4990B. This value is defined as "modern carbon" referenced to AD 1950.
Some archaeologists use the lowercase letters bp, bc and ad as terminology for uncalibrated dates for these eras. Beginning in 1954, metrologists established 1950 as the origin year for the BP scale for use with radiocarbon dating, using a 1950-based reference sample of oxalic acid. Currie Lloyd: The problem was tackled by the international radiocarbon community in the late 1950s, in cooperation with the U. Radiocarbon measurements are compared to this modern carbon value, and expressed as "fraction of modern" (f M).
Whatever, acronyms and abbreviations add colour and texture to the written and spoken word, and to life in general.Take the word , as in Weird Al Yankovic, the man who has had such fun parodying Pharrell of late.When first used, that word meant "having the power to control the fate or destiny of human beings." And that is certainly not the meaning we invoke when referring to Mr. (Before the Present) is the number of years before the present. For example, the entry of humans into the New World during the Pleistocene (Ice Age) is thought to have occurred by about 15,000 years ago, or 15 ka (which is equivalent to approximately 13,000 B.