Radiocarbon analysis of dissolved organic carbon from ice cores

• Main Author: Fang, Ling
• Format: Thesis
• Language: unknown
• Published: Universität Bern 2020
• Subjects: 540 Chemistry; 570 Life sciences; biology; ice core
• Online Access: https://dx.doi.org/10.48549/2363; http://boristheses.unibe.ch/2363/

This thesis provided the first comprehensive evaluation of the great potential of applying radiocarbon analysis of the dissolved organic carbon (DOC) fraction in ice cores at different time scale. Before large-scale human activities (biomass burning, fossil fuel burning, land use etc.), DO14C analysis was used to determine the age of the ice. After the industrialization, radiocarbon analysis can be used for investigating the anthropogenic perturbation to carbonaceous aerosols. Aerosols have very different regional scale distribution due to their short atmospheric lifetime and the uneven distribution of emissions sources. In this thesis, the first complete high-resolution carbonaceous aerosol record with the corresponding fossil and non-fossil contributions was reconstructed from the Fiescherhorn glacier ice core (3900 m asl., Swiss Alps). The total carbonaceous aerosol increased by a factor of three at the end of the 20th century compared to the pre-industrial background. Fossil fuel combustion contributed up to ~32% of the increase. Element carbon (EC) had highest values in the first half of the 20th century, to a large extend caused by fossil fuel emissions. In contrast, Organic carbon (OC) showed a strong increasing trend since 1940s, mostly of non-fossil origin, due to the enhancement of SOA formation.