BERLIN — A group of small island states that include Antigua and Barbuda and the Bahamas secured a win on climate change in an international court Tuesday as they seek to combat rising sea levels.

In its first climate-related judgment, the International Tribunal for the Law of the Sea, or ITLOS, said that greenhouse gas emissions absorbed by the ocean are considered marine pollution and countries are obliged to protect marine environments by going further than required under the Paris climate agreement.

The opinion was requested by a group of nine island nations facing climate-driven rises in sea levels.

The opinion is not legally binding, but it can be used to help guide countries in their climate policy and, in other cases, as legal precedent.

“The ITLOS opinion will inform our future legal and diplomatic work in putting an end to inaction that has brought us to the brink of an irreversible disaster,” Antigua and Barbuda Prime Minister Gaston Browne said.

The other nations in the group that brought the case were Tuvalu, Palau, Niue, Vanuatu, St.Lucia, St. Vincent and the Grenadines, and St. Kitts and Nevis.

The court said states are legally obligated to take all necessary measures to achieve the goal of keeping global warming to 1.5 degree Celsius above preindustrial levels according to the U.N. Convention on the Law of the Seas.

In the case hearings in September, China, the world’s biggest carbon polluter, had challenged the islands’ request, arguing that the tribunal does not have general authority to issue advisory opinions. Beijing said its position was taken to avoid the fragmentation of international law.

“If ITLOS were to find that such an obligation exists, Beijing’s response would most likely be to characterize this as falling outside of its proper scope of authority,” said Ryan Martinez Mitchell, law professor at the Chinese University of Hong Kong.

Eselealofa Apinelu, a representative of the South Pacific island of Tuvalu, said the advisory opinion spells out the legally binding obligations of all states to protect the marine environment and the states against the existential threats posed by climate change.

“This is a historic moment for small island developing nations in their request for climate justice, an important first step in holding the major polluters accountable, for the sake of all humankind,” Apinelu said.

Climate activists and lawyers said the decision could also influence two upcoming legal opinions by the Inter-American Court on Human Rights and the International Court of Justice, which are also considering states’ climate obligations.

Last month, the European Court of Human Rights issued a historic ruling in favor of plaintiffs who argued that Switzerland was violating their human rights by not doing enough to combat climate warming.

“Now we have clarity on what states are obligated to do, which they have failed to do through 30 years … but this is the opening chapter,” Payam Akhavan, lead counsel for the nine island nations in the proceedings, said of the ITLOS opinion, adding that the next step was to ensure that major polluters would implement their obligations.
…