The Arctic is currently warming faster than the global average, resulting in the wide-spread thaw of permafrost deposits, increased degradation of thawed organic matter to greenhouse gases as well as the transfer of permafrost-derived material to aquatic systems. The vast and shallow shelf seas north of Siberia receive large amounts of both carbon and nitrogen from thawed permafrost by strong coastal erosion (up to several meters per year) and by large rivers such as Ob, Yenisey and Lena. The fate of nitrogen released to the ocean has received little attention so far and remains a large source of uncertainty. Nitrogen cycling can influence greenhouse gas budgets (1) directly, by release or consumption of the strong greenhouse gas nitrous oxide (N2O), and (2) indirectly as nitrogen and carbon cycling are closely coupled and nitrogen availability is one of the factors limiting primary production in the Arctic Ocean.
These two connected projects focus on N2O emissions and nitrogen cycling on the Siberian Arctic Ocean shelves, aiming to (1) quantify N2O fluxes between ocean and atmosphere, (2) identify the main N2O sources, and (3) identify the role of permafrost-derived nitrogen delivered by rivers and coastal erosion.
The work is link to the ISSS-2020 Arctic Ocean Expedition: