An international ocean court has just delivered a “historic” legal opinion outlining countries’ obligations in the face of climate change. The International Tribunal for the Law of the Sea (ITLOS) – a UN court on maritime law – found that anthropogenic greenhouse gas emissions can be considered a marine pollutant. It said countries have a legal obligation to implement measures mitigating their effect on oceans. ITLOS’s expert opinion was requested last September by a group of nine small island states in the Pacific and Caribbean threatened by rising sea levels: the Commission of Small Island S…