Large scale circulation

The inflow of warm and salty water from the Atlantic is a major driver of observed changes in the Arctic, including the thinning of the sea ice cover. The contributions of the different pathways of the Atlantic Water into the Arctic are investigated here. The thinning of the sea ice is likely to further contribute to an acceleration of the sea ice drift.

Sunset over thin ice in the Arctic

Thin ice is easier to break up and advect by swell and ocean currents. Photo: Angelika Renner / Norwegian Polar Institute

In recent years, all major components of the Arctic sea ice regime have been changing. Prolonged ice melt in the summer and unusual weather conditions have been observed together with more sea ice exiting and more warmer water from the Atlantic entering the Arctic Ocean. The decrease in the area covered by sea ice and the thinning of the ice then caused changes in the drift of the ice. Variations in the inflow of warm and salty Atlantic water to the Arctic through the Fram Strait and the Barents Sea are a major driver of changes in the sea ice cover conditions. To confirm the importance of the Atlantic Water inflow and to investigate the pathways of the Atlantic Water into the Arctic, we will collect new data from the Fram Strait, the northern Barents Sea, and the waters north of Svalbard, and combine these observations with historical datasets for analyses on seasonal and interannual timescales.

The thinner Arctic sea ice cover will behave differently than what we have seen so far. Measurements using radiosounding systems will provide us with further insight into the vertical structure of the atmosphere and its role in driving the changes. With datasets of sea ice drift and concentration as well as atmospheric observations and in situ measurements of ice thickness and ice motion, we will test whether the sea ice drift in the Arctic will continue to accelerate.