The understanding of critical small-scale processes in the Arctic Ocean – particularly energetic (sub) mesoscale eddies – remains fundamentally limited, hindered by sparse observations and the inherently small spatial scales. Yet, emerging evidence reveals these processes are important for climate change: driving upward heat flux, modulating atmosphere-ice-ocean exchanges, redistributing biogeochemical constituents, and directly impacting sea ice dynamics, stratification, and circulation. As the Arctic transforms under warming climate – marked by decreasing ice cover, altered seasonality, and intensified air-sea coupling – the prevalence and influence of these fine-scale dynamics will evolve, potentially altering climate feedbacks in the Arctic. This session seeks contributions leveraging theory, modeling, and observations to illuminate the generation, interactions, and impacts of (sub)mesoscale and smaller scale processes. This includes understanding their role in transports (heat, nutrients, freshwater, energy), their representation in ocean models, their effects on basin-scale circulation, and their evolution in a changing Arctic. Interdisciplinary studies about the coupled ice-ocean-atmosphere system, biogeochemical responses, and ecosystem consequences are strongly encouraged.