Application of AMS radiocarbon in earth system science studies

Radiocarbon, a cosmic ray-produced isotope, is one of the most important tr acers in Earth system sciences. The strong involvement of carbon in the bio sphere and its half life of 5720 years are reflected in appropriate applica tions in archeology, as well as in the Earth system sciences. Radiocarbon d ating had an important turning point in 1977 with the discovery that mass s pectrometry with tandem acceleration could be used to measure C-14. This ne w technique, known as AMS or accelerator mass spectrometry reduced the requ ired sample size to the order of mg, three orders of magnitude smaller than for conventional techniques, thus opening the range of applicability of C- 14 studies to a much wider range of samples. However, the application has b een complicated by two major activities of human beings on a global scale: the extensive usage of fossil fuel since the industrial revolution and nucl ear testing in the atmosphere, which have influenced the natural balance of radiocarbon in the atmosphere. However, the separation of bomb-produced ca rbon from natural background carbon has produced a very fruitful understand ing of the global carbon cycle and the conveyor belt system in the ocean, w hich will be essential for understanding global environmental problems, suc h as global warming, in the coming century. Carbon cycle studies in Korea h ave been made since the early 1990s. The studies include monitoring of CO2 concentrations in the atmosphere, stable isotope studies, and carbon cycle studies in the sea around Korea. The opening of the AMS facility at Seoul N ational University (SNU) will enhance carbon studies in Earth system scienc es greatly in the future.