Atmospheric and Oceanic Radiocarbon Systems 
 

This activity uses radiocarbon as tracer and chronometer of atmospheric and ocean processes. 

Collecting corals, Cocos-Keeling Island, Indian Ocean

The Atmospheric and Oceanic Radiocarbon Systems activity investigates variations in atmospheric transport, ocean circulation, sea-surface temperatures and rainfall histories by measuring radiocarbon, stable isotopes and trace elements archived in tree rings, corals and speleothems.

The project focuses on the tropics and Southern Hemisphere, and uses radiocarbon as a tracer and chronometer to better understand climate processes and variability in both modern archives (such as using the radiocarbon bomb pulse) and in ancient archives to better predict future climate change.

Comparisons of these records across continental and oceanic sites are used to understand the mechanisms of abrupt climate change, i.e., the frequency and intensity of El Niño/Southern Oscillation (ENSO) cycles in the past, and to characterise Asian monsoons, among other things.

As these paleoclimate studies require a precise and accurate chronological framework, the task also aims to improve the radiocarbon dating method in terms of calibration, methodology and dating of inter-comparisons from different materials.

Specific studies

• Atmospheric bomb ¹⁴C data for age calibration

• Bomb ¹⁴C in tree rings from South East Asia and Australia

• Dating of Angkor Civilisation, Cambodia

• Evolution of reef islands

• Growth rates of Antarctic mosses derived from radiocarbon

• High-resolution climatic and rainfall records from Australian speleothems

• High-resolution climatic records from corals, Kirabati in the central Pacific

• High-resolution climatic records from corals, the Cocos (Keeling) Islands in the Eastern Indian Ocean

• Marine radiocarbon reservoir corrections and ocean circulation

• Radiocarbon calibration

• Radiocarbon dating of recent tree rings

• Regional atmospheric ¹⁴C offsets and and atmospheric circulation.