New research is highlighting the significant impact of climate change on the world’s oceans. Energy systems are at risk from the effects, which include rising sea levels. At the same time, renewable energy from the ocean, such as offshore wind, will play a role in advancing the energy transition. What will energy systems need to operate given the impact of climate change on our oceans? What role will oceans play in the energy transition? What effect will the energy transition have on oceans as the climate continues to change?