To what extent will constraining sea-ice-cloud feedbacks reduce uncertainty in our understanding of Arctic amplification and global climate sensitivity? Both observations and modelling studies have evidenced the importance of polar clouds (and aerosol) in controlling the surface energy budget at high-latitudes. High-latitude clouds are highly sensitive to changes in aerosol concentration and strongly coupled to sea-ice processes. Thus, our expectation is that high-latitude clouds will fundamentally change in a warming world with the potential to both mitigate or enhance warming at high-latitudes. However, both high-latitude cloud and aerosol have (historically) been poorly simulated in global climate models and across CMIP6 we predict significant variation in model outcomes with respect to high-latitude cloud forcings. In this project we will quantify the importance of sea-ice cloud feedbacks across CMIP6 ensembles and estimate the impact of constraining this feedback on our understanding of Arctic amplification and global climate sensitivity.