Skip to main content

Talos Dome ice core Climate-related variability of Iron, CO2 and Carbon isotopes in the Southern Ocean

Final Activity Report Summary - TDICOSO (Talos Dome ice core ? Climate-related variability of Iron, CO2 and Carbon isotopes in the Southern Ocean.)

The project ‘Talos Dome ice core - climate-related variability of iron, carbon dioxide and carbon isotopes in the southern ocean’ (TDICOSO) involved the study of an Antarctic ice core in order to better understand the dynamics of the climate of the southern ocean. The Earth’s climate was characterised for the past 800 000 years by fluctuations from glacial, cooler, to interglacial, warmer, conditions, accompanied by variations in the atmospheric content of carbon dioxide and dust as well as in the oceanic content of biota, largely phytoplankton. The aim of TDICOSO project was to study the interactions of these climatic components during the past two glacial cycles, as they were archived in an Antarctic ice core which was drilled at Talos Dome in coastal east Antarctica.

The Talos Dome ice coring effort was an Italian-French collaborative drilling project, which resulted in a 1 600 m long ice core drilled between 2004 and 2008, offering a high resolution record of the past two glacial cycles, covering approximately the past 250 000 years. The concentration of iron (Fe) was measured in one metre long sections of Talos Dome ice using an inductively coupled plasma sector field mass spectrometer (ICP-SFMS). Collaborating laboratories analysed concentrations of carbon dioxide and carbon isotopes in the gas that was contained in air bubbles locked in the ice.

The iron concentrations showed great changes from glacial to interglacial climate conditions and indicated that there were similar patterns of iron concentrations at Talos Dome and Dome C in central east Antarctica. Furthermore, it was demonstrated that iron concentrations varied independently in dust and other crustal elements, indicating that specific elemental tracers might be preferable to total dust or dust proxies when modelling the carbon cycle or dust-related climatic processes, such as the southern ocean biological pump. There appeared to be distinctive variations in Fe fluxes in the Antarctic continent, which could potentially be a useful method to verify the synchronicity of Antarctic ice cores. Further insights would be available by the time collaborating laboratories completed their analyses of the Talos Dome ice core.