Climate models are considered essential tools for estimating the future climate and for preparing ourselves for the effects. But there are also uncertainties associated with the models, especially in the Arctic region, due to relatively few observations of important polar processes. CRiceS aims to give improved knowledge, identify model shortcomings, and contribute to more precise climate models for the Arctic. 

In a new article from CRiceS researchers, Morven Muilwijk shows that one central weakness of current models is how they conclude about the stratification in the Arctic Ocean.

Politicians around the world use climate models as a basis for decisions. It is then important that they contain as little uncertainty as possible, says Muilwijk.

In the northern Barents Sea and the area north of Svalbard, the warm Atlantic water from the south meets cold Arctic water. The salty and warm Atlantic water is heavier than the cold and relatively fresh water in the Arctic Ocean.

The layering "protects" the sea ice because it prevents the heat from the Atlantic layer from melting the ice from below. The process is very decisive for how the sea ice develops. But it is also important how the world of research understands the changes in the sea.

The climate models have a too deep and too cold Atlantic layer, which means that they underestimate the effect of the ocean on Arctic warming. Furthermore, they differ in the future development of this process. About half of the models predict  a strengthening in stratification and the other half a weakening in the coming century. This makes it difficult to calculate the consequences of future warming in the Arctic, says Muilwijk.