Organic matter characteristics in yedoma and taberal deposits in Siberia
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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.
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AWI Organizations > Geosciences > Junior Research Group: PETA-CARB