The recent severe winters experienced over the Eurasian continent have attracted much attention, in particular because of an observed association with sea ice cover in the Barents- Kara Sea. This topic is particularly challenging to study because the relationship between sea ice and Eurasian winters manifests differently in reanalysis data compared to climate models (see selected Bjerknes publications below). As a result, even after a very active decade or so of research, we continue to see conflicting messages in the literature – some studies suggest that sea ice is critical for Eurasian cooling (e.g., Mori et al. 2019) while others suggest that it plays a minor role (e.g., McCusker et al. 2016, Blackport et al. 2019). Issues to address: intermittency, robustness, signal-to-noise, model dependence, modulation by multidecadal variability, role of ocean variability and feedbacks, coupled versus uncoupled viewpoints.

Given the depth of experience in Arctic-midlatitude teleconnections at BCCR and our track- record of publishing high-quality articles on Eurasian cooling, we feel we are well-positioned to review, synthesize, and make sense of the large body of literature on this topic. Especially for newcomers to the topic, such a paper would help highlight what the community has learned about the role of sea ice in Eurasian cooling, why uncertainties remain, and where fruitful future research directions lie. The activity of writing the proposed paper will serve to bring together various Bjerknes researchers already working in the field, engendering stronger collaboration and coordination between these researchers for future projects and proposals.