Human activities are driving major changes in the oceans of the world. One key driver of changes is elevated carbon dioxide (CO2) concentration in the atmosphere caused by human activities. This leads to ocean acidification, warming and deoxygenation, changes in ocean circulation, continued sea level rise, and an altered marine productivity and biodiversity. Other key drivers are pollution with nutrients, chemicals and plastic, overfishing and spreading of invasive species. All of the changes in the ocean have profound effects on human wellbeing and human societies in many regions of the Earth.

The G7 Academies of Sciences call for:

• (1) changing the course of nations’ CO2 emissions,
• (2) reducing and further regulating man-made pollution of the sea,
• (3) ending overfishing and preserving marine biodiversity and ecosystem function through research-based management and
• (4) enhancing international scientific cooperation to better predict, manage and mitigate future changes in the ocean, and their impacts on human societies and the environment.