Organic matter characteristics in yedoma and taberal deposits in Siberia

• Main Authors: Jongejans, Loeka L., Strauss, Jens, Mangelsdorf, Kai, Lenz, Josefine, Grosse, Guido
• Format: Conference Object
• Language: unknown
• Published: 2018
• Subjects: Arctic; Climate change; Ice; permafrost; Thermokarst; Alaska; Siberia
• Online Access: https://epic.awi.de/id/eprint/48673/; https://hdl.handle.net/10013/epic.09627a13-b577-4e28-bd50-813d8254c696

With ongoing climate change, the Arctic will continue to warm approximately twice as fast as the lower latitudes. As large parts of the Arctic are affected by permafrost, large-scale degradation processes such as thermokarst and thermal erosion, will accelerate. As a legacy of the last ice-age, ice-rich permafrost, such as yedoma permafrost, covers large areas in Alaska and Siberia. These deposits can reach a thickness up to 50 m and are prone to deep degradation, due to a ground ice content up to 90 vol%. Moreover, undisturbed yedoma deposits contain organic carbon (OC) of high quality which is presumably highly vulnerable to future microbial decomposition. Climate warming of these deposits can mobilize OC even well below 1 m soil depth. In the proposed dissertation project, I aim to assess the vulnerability of ice-rich permafrost landscapes to future permafrost thaw, and the quality and size of the OC pool. Both tasks are crucial to assess future greenhouse gas release rates. Therefore, I will combine Arctic field, state-of-the-art laboratory analysis and statistical analysis on samples from this highly vulnerable part of the earth. The project is crucial in the understanding of OC characteristics in ice-rich permafrost, which is the basis for reliable Arctic climate predictions by illuminating biogeochemical processes influencing greenhouse gas release from vast regions in the warming terrestrial Arctic.