States have legal duty to cut greenhouse emissions, says top maritime court

Greenhouse gases are pollutants that are wrecking the marine environment, and states have a legal responsibility to control them, an international court has stated in a landmark moment for climate justice.

Wealthy nations must cut their emissions faster than their developing peers, the court also decided.

The statements were part of an advisory opinion on climate change issued on Tuesday by the international tribunal for the law of the sea (Itlos). The tribunal is responsible for interpreting and upholding the 1982 UN convention on the law of the sea (Unclos), an international treaty representing 169 countries.

It is the first time such a document has been issued by an international court.

The opinion was requested by the Commission of Small Island States on Climate Change and International Law (Cosis), a group of nine Caribbean and Pacific island nations led by Antigua and Barbuda and Tuvalu, who are particularly vulnerable to climate breakdown and had become frustrated with the pace of international talks.

In its unanimous opinion, the tribunal stated that the oceans are warming and becoming more acidic as a direct result of carbon dioxide emitted from human activities, resulting in harm to living resources and marine life, hazards to human health and hindrance to marine activities such as fishing.

In their submissions to the tribunal, most countries accepted that greenhouse gases were a form of pollution, but they disagreed on how exactly governments should have to respond to that threat.