Groundbreaking climate opinion from international court – States must go further to address GHG emissions

States must take “all necessary measures” to prevent, reduce and control greenhouse gas (GHG) emissions from any source – simply participating in global efforts is not necessarily enough.

(Hamburg, Tuesday, 21 May 2024) Today in Hamburg, Germany, The International Tribunal for the Law of the Sea (ITLOS) has handed down a highly-anticipated advisory opinion, marking a historic moment in international climate law. The opinion clarifies States’ obligations under the United Nations Convention on the Law of the Sea (UNCLOS) with respect to impacts from anthropogenic climate change on the marine environment.

The advisory opinion is a response to a request by a collective of small island states called the Commission of Small Island States on Climate Change and International Law (COSIS), which was issued in December 2022.

ITLOS has confirmed that human-caused greenhouse gas emissions constitute “pollution of the marine environment” and that States therefore must comply with a wide-ranging set of obligations under UNCLOS. These include, among other things, taking “all necessary measures” to prevent, reduce and control GHG emissions from any source - an objective standard which must be informed by the best available science and the 1.5-degree temperature goal of the Paris Agreement. The Tribunal has also made clear that simply participating in global efforts is not necessarily enough to meet this standard. 

Our Legal Director, David Kay, commented:

“This is a seminal moment for international climate change law. The judges were clear that given the high risks of serious and irreversible harm to the marine environment, states’ obligations to address GHG emissions need to meet a very high standard, informed by the best available science and the 1.5 degree temperature goal and timeline. It’s not enough to just rely on global efforts and international organisations. With sectors such as international shipping currently off course, States urgently need to put in place effective policies to meet these legal obligations.”

This advisory opinion by ITLOS is expected to have significant, far-reaching implications – not least, informing policy-making at the domestic and supranational level. At the International Maritime Organization (IMO) this September, States will continue important negotiations around the ‘basket of measures’ that will support the delivery of the Revised GHG Strategy agreed last year. This advisory opinion should play a crucial influential role in these international negotiations, as the Tribunal has clarified States’ obligations under the law of the sea to protect our ocean from the impacts of anthropogenic climate change, including international shipping.

Last year, Opportunity Green put forward a supporting submission to ITLOS urging the Tribunal to consider international shipping emissions in its opinion. The submission called on the Tribunal to clarify countries’ legal obligations to stop the pollution of the marine environment and protect it from climate change impacts. This is of utmost importance because the emission targets of the IMO 2023 GHG Strategy fall short of meeting the 1.5°C temperature goal of the Paris Agreement, and the accompanying regulatory measures are currently being negotiated by Member States, with a view for adoption by next year.

Isabela Keuschnigg, Legal Officer at Opportunity Green, says:

“With ongoing climate change cases around the world and three international advisory proceedings in the context of climate change, this is a pivotal moment in the pursuit of climate justice. ITLOS is the first of the three international courts and tribunals that has issued its opinion and will inevitably set the scene for what is to come. The Tribunal has shown the significance of our ocean in tackling the climate crisis and, crucially, highlighted the role of the law of the sea which clearly calls on States to take all necessary measures to stop the pollution of our seas from anthropogenic climate change.”

Opportunity Green will be assessing the results of the advisory opinion in detail and will be issuing more in-depth analysis once our legal team has had the opportunity to review and digest the advisory opinion in full.

Notes to editors

Opportunity Green is an NGO working to unlock the opportunities from tackling climate change using law, economics, and policy. We do this by amplifying diverse voices, forging ambitious collaborations and using legal innovation to motivate decision makers and achieve climate justice, with particular emphasis on the aviation and shipping industries.

Global shipping is a major greenhouse gas (GHG) emitter (responsible for about 3% of global emissions, a figure which is set to rise dramatically without significant intervention) that significantly contributes to the climate crisis. Yet efforts by the global regulator, the International Maritime Organization (IMO), are not yet on track to meet the 1.5°C temperature goal of the Paris Agreement.

Opportunity Green’s submission to the Tribunal outlined the following points:

• UNCLOS requires States to take all necessary measures to prevent, reduce and control pollution of the marine environment including GHG emissions from vessels in line with the 1.5°C temperature goal of the Paris Agreement;

• As long as climate policies enacted by the IMO remain unaligned with the Paris Agreement temperature limit, States are failing to meet their obligations under UNCLOS;

• Moreover, considering the inadequacy of existing IMO standards, States can and should adopt more stringent unilateral or regional standards to meet their obligations under UNCLOS.