Understanding the Atlantification Process in the Arctic through Long-term Data Analysis of the North Atlantic, Barents Sea, and Fram Strait.
Supervisor: Amaia Orbea
Atlantification is the process by which the Arctic Ocean is becoming progressively warmer and saltier due to the increasing influence from Atlantic Water (AW) inflow. As a result of the combined  effects of Atlantification and anthropogenic climate change, sea ice is disappearing, reducing in both coverage and thickness. This in turn enhances oceanic warming which furthers sea ice melt. In this thesis, we investigate the covariance between sea ice dynamics and oceanic thermohaline properties over the time period 1980 – 2023. Four regions: the southern boundary (66ºN), Barents Sea Opening (BSO), East Fram Strait (EFS) and West Fram Strait (WFS) were selected in order to analyze AW evolution as it travels into the Arctic. We find that while temperature, salinity, sea ice thickness, and sea ice

concentration are highly variable on annual and interannual scales, it is possible to pick out some long term trends. It is clear that sea ice and thermohaline properties have altered significantly, in particular with regards to a regime shift that occurred in 2007, after which sea ice is found at lower volumes and AW is found with higher temperatures. Both AW inflow and sea ice reduction affect Arctic Ocean properties, with physical and ecological implications not yet fully understood. It is therefore still important to better understand the covariability of oceanic and sea ice interactions.