Research Student 2012
Climate Change and Earth-Ocean-Atmosphere Systems
Radiocarbon Evidence of Ocean Circulation Change over the Last deglaciation
The rise in atmospheric CO2 at the end of the last glacial maximum, is well documented, yet the source remains unproven. A synchronous drop in 14C of atmospheric CO2 occurred which has lead to the proposal that CO2 was released from a radiocarbon depleted oceanic abyssal reservoir which had been isolated from the atmosphere for several thousand years. It has been suggested that the radiocarbon depleted CO2 water, when released, exited from the Southern Ocean and was transported via Antarctic Intermediate Water, AAIW. Observations however are currently conflicting and further work needs to be done to unravel the mystery of the deglacial CO2 rise. This project looks at the radiocarbon ages of intermediate-deep waters to infer changes in ocean circulation including; major water mass distribution, ocean stratification and rates of carbon dioxide exchange over the deglacial. By combining this data with other proxies including δ13C, δ18O, proxies for oxygenation of bottom waters such as U/Ca and εNd, changes in ocean structure and in particular carbon storage can be inferred.
Supervisor: Luke Skinner