Master thesis defense by Maureen Eyers Bøge Jørgensen

Title: Optimizing an O2 extraction system to measure atmospheric δ18O in ice core 

Abstract: Understanding past climate changes is important to benchmark and improve future climate model projections. Past climate proxies obtained from sources, such as ice cores, contain a wealth of diverse paleo-environmental information at relatively high temporal resolution. Isotopic composition of atmospheric O2 is important for tracing biological and hydrologic
processes. Furthermore, measuring δ18O conserved in bubbles in ice core can be used a global marker as the time scale for interhemispheric mixing of atmospheric O2 is one year. This project focuses on experimental work to reassemble and optimize the O2 extraction system at Physics of Ice and Climate at the Niels Bohr Institute. The extraction system enables further measurement of atmospheric δ18O in ice cores in an Isotope Ratio Mass Spectrometer. Testing of NEEM ice core at the end of the project provided results that were analyzed for further optimizing of the extraction system.

Supervisor: Thomas Blunier

Censor: David Morten Balslev-Harder (DFM)