Recently published research conducted on an ice core from Mount Elbrus in the Caucasus region aimed to reconstruct the history of organic carbon (OC) aerosol over southeastern Europe by analyzing dissolved organic carbon (DOC) and its radiocarbon (¹⁴C) signature (DO¹⁴C). This study highlighted the changes in OC aerosol composition from the pre-1945 era to recent years, showcasing an increase in DOC concentrations by 45% post-1960 and a mean DO¹⁴C depletion of 32% in recent Elbrus ice relative to atmospheric ¹⁴CO₂ mainly attributed to fossil fuel sources.

During the bomb-peak era (1955–1980), the DO¹⁴C content closely mirrored the changes in atmospheric ¹⁴CO₂ indicating that the living biosphere was the primary source of biogenic DOC in summer. This contrasts with findings from Alpine ice in western Europe, where a post-1950 doubling of DOC was linked to increased organic compound emissions from vegetation due to use-land changes and global warming. The study also documented the first-time winter changes in DOC and DO¹⁴C, showing a 44% increase in DOC levels and a 47% lower ¹⁴C signature compared to atmospheric ¹⁴CO₂ in Elbrus ice after 1960. The winter ¹⁴C record suggested that biogenic emissions from the living biosphere and a minor contribution from wood burning were the primary sources of DOC in this season.

This research, "20th Century Changes of DOC and Its ¹⁴C Signature Archived in Caucasus Ice-Core: Implications for Past Sources of Organic Carbon Aerosol in South-Eastern Europe," was an international collaboration published earlier this month in JGR Atmospheres. The Ohio State University's School of Earth Sciences and Byrd Center Researcher Stanislav Kutuzov was a co-author of the study.

This research emphasizes the importance of understanding past aerosol load and composition for climate change studies. It highlights the significant role of natural versus anthropogenic sources in the OC aerosol budget and the variability of these sources in response to climatic and environmental changes. The findings from Mount Elbrus offer valuable insights into the regional differences in OC aerosol sources and underscore the need for further studies to fully comprehend the past and present dynamics of OC aerosols in Europe.

To learn more about the study, Visit JRG Atmospheres or download the PDF.