Nitrogen cycling in the warming Arctic Ocean ...

• Main Author: Doncila, Antonia
• Format: Article in Journal/Newspaper
• Language: English
• Published: The University of Edinburgh 2022
• Subjects: Arctic Ocean; stable isotopes; nitrogen cycling; nutrients; global warming; Biogeochemistry; Arctic; Barents Sea; Fram Strait; Global warming
• Online Access: https://dx.doi.org/10.7488/era/2067; https://era.ed.ac.uk/handle/1842/38813

This PhD thesis is investigating fixed nitrogen cycling at a Pan-Arctic scale, in order to better understand the sensitivity of Arctic biogeochemistry to ongoing warming and to identify future implications for long-term carbon fixation, nitrogen mass balance and oxygenation of the Arctic Ocean. Using stable isotopes of nitrate (δ¹⁵N-NO3 and δ¹⁸O-NO3), alongside an extensive suite of biogeochemical and hydrographic data, this project provides spatially and temporally integrated measurements of N supply, uptake and recycling in the Central Arctic Ocean (Nansen, Amundsen and Makarov basins) and the Atlantic inflow regions (Barents Sea, Fram Strait), outlining the processes that control nutrient budgets and fluxes on a Pan-Arctic scale. This study proves the paramount role of bordering Arctic shelves in the reprocessing and redistribution of nutrients throughout the entire Arctic Ocean. Stable isotope data demonstrates that the entire nutrient pool in the Central Arctic halocline has been regenerated and ...