Raman spectroscopy of micro-inclusions in Antarctic ice cores
Dr. Christian Weikusat
Helmholtz-Zentrum für Polar- und Meeresforschung
The climatologic interpretation of greenhouse gases extracted from inclusions in ice cores is hampered by a severe lack of knowledge about the processes governing their entrapment and subsequent evolution. The transition from air bubbles to clathrates can significantly alter the gas mixing ratios, due to processes which are little understood. High-resolution CO2 measurements indicate, that the speed of the enclathration process varies substantially, even between neighbouring layers. Linescanner data reveal peculiar clear layers, where the bubble-clathrate transition is already completed, throughout the transition zone. With Micro Raman spectroscopy, gas contents of individual inclusions can be analysed. The spectrometer at AWI Bremerhaven provides unprecedented spatial resolution and is optmized for fast automated mapping acquisitions. To improve our understanding of the above mentioned processes and observations, the hereby proposed project will include systematic mapping of the gas contents of bubbles/ clathrates inside significant layers, mapping and comparison of whole clathrate clusters to determine the formation path and mapping and identification of solid inclusions to determine their role in nucleation.
Förderung von 2010 bis 2015