Far north of any coastline, at the top of the world, lies the least-disturbed marine ecosystem left on Earth. The Central Arctic Ocean (CAO) – the ‘high seas’ region surrounding the North Pole – has throughout human history been protected by the natural barrier created by its sea-ice cover.

That natural barrier is now thinning and retreating. And with it, a new question is emerging for ocean governance. How can this region’s biodiversity be protected as vessel access becomes increasingly possible? Can a legal barrier replace nature’s melting one?

A United Nations report (December 2025) commissioned by 90 North Foundation, produced in collaboration with the World Maritime University, The Arctic Ocean Region: Biodiversity, Governance and Protective Measures, examines this urgent question in depth. The report assesses the ecological significance of the wider Arctic Ocean, the evolving framework of international governance, and the growing pressures facing this remote marine environment from vessel-based commercial activities. One of its conclusions is pragmatic: the international community should consider designating the Central Arctic Ocean as a Particularly Sensitive Sea Area (PSSA).

The CAO’s unique characteristics include year-round sea-ice cover, surface water temperatures hovering around 0ºC, and three months of starlight-only winter darkness. Consequently, the world’s only polar ocean hosts highly specialised species that have adapted to life in these extreme conditions; and for many, their recovery from disturbance is known to be slow, making them especially vulnerable to the impacts, stressors, and risks generated by vessel-based industrial activity.

Although scientific understanding of the CAO is still developing, researchers increasingly recognise its importance as a reservoir of biodiversity and associated genetic resources, and as a regulator of global climate systems. From plankton communities living within sea ice to migratory marine mammals and seabirds that traverse the basin, the Arctic marine ecosystem is tightly interconnected and highly sensitive to change.