The AAORIA 2025 Polar Side Event “Polar Oceans and Climate: Advancing Synergies for Long-Term Global Collaboration”, held on 24 September 2025 in Brussels, brought together leading scientists, policymakers, and representatives from international organisations to highlight the essential role of the polar regions in the Atlantic Ocean and global climate systems. The meeting showcased how polar science contributes to the AAORIA priorities and the All-Atlantic Declaration, reinforcing the need for joint research, innovation, and policy coordination across the Arctic, Antarctic, and Atlantic. Throughout a day of engaging presentations and discussions, participants emphasised that advancing knowledge of the polar regions and their connection to the Atlantic Ocean is fundamental to anticipating climate change, protecting biodiversity, and sustaining the communities and economies that depend on a healthy ocean. The event concluded with a Call for Action affirming that investment in polar research is an investment in security, sustainability, and resilience for the Atlantic and the planet. Governments, research institutions, and funding agencies were urged to elevate polar science as a global priority, transforming knowledge from the world’s coldest regions into collective action for a sustainable ocean and a resilient future.