Seasonal Influence of the Atmosphere and Ocean on the Fall Sea Ice Extent in the Barents-Kara Seas

The fall sea ice in the Barents and Kara (B-K) Seas has shown important influence on the northern extratropical climate in the following winter. Utilizing the reanalysis and observational data, we investigate the role of the atmosphere and ocean in shaping the fall B-K sea ice extent with 1-12 months lead time. In the ocean, the warm sea surface temperature in the B-K open water from the previous winter to early fall is the most important and persistent contributor to sea ice melt. In the atmosphere, the relatively warm air and dynamic weather systems over the B-K Seas have potential to directly drive the sea ice variability at the lead time of 1-2 months. Furthermore, significant signals are found as early as the previous winter, although they might become weak during the melting season. Empirical models are constructed with different optimal predictors selected based on these physical mechanisms. These models produce skillful predictions of the fall B-K sea ice extent on seasonal and monthly scales. These results can enhance the understanding of the fall sea ice variability and provide helpful information for making stakeholder-relevant decisions.

Automated summary

The fall sea ice in the Barents and Kara Seas is influenced by both the atmosphere and ocean, with sea surface temperature and atmospheric weather systems playing key roles in shaping sea ice extent. Models constructed based on these physical mechanisms show skillful predictions of sea ice variability, providing valuable information for decision-making.