A new Australian gas lab for the Million Year Ice Core project

The aim of the Australian Million Year Ice Core Project (MYIC) is to drill and recover an ice core that extends to well over a million years ago. Due to the highly thinned nature of the ice close to the bedrock of the MYIC, good vertical sampling resolution, and thus small sample capabilities, is key to resolve the variability in the climate records. This requirement demands major development of new ice core measurement capability, including a state-of-the-art ice continuous flow analysis facility and development and build of a new ice core gas laboratory.

The main capabilities for the gas laboratory include a small-volume (~50g) sublimation extraction system, a QCL absorption spectrometer, and a MAT 253+ mass spectrometer, to produce 1) concentration measurements of the primary greenhouse gases CO₂, CH₄, N₂O to constrain changes in radiative forcing, 2) isotope ratio measurements of CO₂ on discrete ice samples to screen measured concentrations for contamination artefacts and constrain carbon cycle source and sink changes, 3) measurements of δ¹⁸O-O₂ and δ¹⁵N-N₂ for understanding of site conditions, gas trapping, firnification processes and to aid dating. We present our plans and progress in establishing the new Hobart ice core gas facility to achieve these measurements.