Atlantic Water (AW) is a key driver of change in the Barents Sea. We have studied an emerging pathway of AW into the Barents Sea through the Svalbard Archipelago. We found that the Atlantic sector near the study site has warmed in the recent two decades, that Atlantic-origin waters intermittently enter the Barents Sea through this pathway, and that the heat transport is driven by tides, wind events, and variations in the current system upstream.

In the northwestern Barents Sea, we study the Barents Sea Polar Front formed by Atlantic Water meeting Polar Water. Analysis of ship and glider data between October 2020 and February 2021 show a density front with warm, salty water intruding beneath cold, fresh. Short-term variability is linked to tidal currents and mesoscale eddies, influencing front position, density slopes, and water mass transformation. Despite seasonal changes in the upper layers, the front remains stable below 100 m depth.

The Multidisciplinary Observatory for the Study of Arctic Climate project has collected a rich data set in the central Arctic. This paper presents ocean model reanalyses of the part of the MOSAiC. More than 630,000 single data points and over a thousand profiles were used by the model. The results allow for analyzing the distribution of temperature, salinity, and velocity. The model provides insights into the eddies dynamics that would not be possible by analyzing the observations alone.

A turbulence instrument was installed on a light autonomous underwater vehicle (AUV) and deployed in the Barents Sea in February 2021. We present the data quality and discuss limitations when measuring turbulence from the AUV. AUV vibrations contaminate the turbulence measurements, yet the measurements were sufficiently cleaned when the AUV operated in turbulent environments. In quiescent environments the noise from the AUV became relatively large, making the turbulence measurements unreliable.

We quantify the mesoscale eddy field in the Lofoten Basin using Lagrangian model trajectories and aim to estimate the relative importance of eddies compared to the ambient flow in transporting warm Atlantic Water to the Lofoten Basin as well as modifying it. Water properties are largely changed in eddies compared to the ambient flow. However, only a relatively small fraction of eddies is detected in the basin. The ambient flow therefore dominates the heat transport to the Lofoten Basin.