The One Ocean Science Congress, organized by CNRS and IFREMER, will be held in Nice, France, from 4 to 6 June 2025. It is a UN Special Event serving as the scientific foundation of the Third United Nations Ocean Conference (UNOC3).

This three-day congress will generate science-based outcomes and recommendations to support the global discussions at UNOC3. It will feature a mix of plenary sessions, including opening and keynote speeches, alongside parallel oral and poster presentations. To enhance interactions between science and society, action and policy, and to engage civil society more broadly, ‘townhalls’ such as panels and roundtables will also be arranged.