The International Court of Justice (ICJ) has issued its ruling on States’ legal obligations in relation to climate change.

In a watershed advisory opinion, the

International Court of Justice (ICJ) in the Hague has said a “clean, healthy and sustainable environment” is a human right, and that failing to protect the planet from the impacts of climate change may be a violation of

international law.

Outlining the obligations of states to protect the human rights of citizens being impacted by rising global tempeartures, the UN’s highest court said the climate must be protected for “present and future generations.”

Reading the ruling, ICJ president Yuji Iwasawa said “greenhouse gas emissions are unequivocally caused by human activities and have crossborder effects” with far-reaching consequences.

These, he said, “underscore the urgent and existential threat posed by climate change.”

Iwasawa said countries have a duty to cooperate on preventing harm caused by climate change and must make sure their national climate targets represent the highest possible ambition.

Largest case in ICJ history

The case began after students from Pacific Island countries lobbied governments into calling for the legal clarification.

The state of Vanuatu requested the ICJ to rule on the obligations of states under international law to protect the climate and environment from greenhouse gas emissions. And by extension present and future generations.

In December, the court heard testimonies from almost 100 countries and 12 international organizations.

Speaking at the time, Gaston Browne, Prime Minister of Antigua and Barbuda, told judges that sea level rise driven by “unchecked emissions” was eroding island coastlines and “swallowing land that is vital to our country.”

The Caribbean archipelago is being eroded by rising sea levels and faces more intense storms as a result of the impacts of a warming world.

Also speaking as part of the December hearings, high-emitting nations, like the United States, said existing UN treaties — primarily the 2015 Paris Agreement — already provide legal obligations on action towards slowing climate change.

President Donald Trump has since announced his country’s withdrawal from the landmark accord that saw 195 nations agree to reduce carbon emissions and pursue efforts to limit global warming to no more than 1.5 degrees Celsius (2.7 Fahrenheit).

But experts say the Paris Agreement was never intended to define all laws around climate change.

How does carbon dioxide cause global warming? To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video

Joie Chowdhury, senior attorney at the Center for International Environmental Law (CIEL) says because rising temperatures affect “almost every possible dimension of our lives,” there is scope for a lot of different laws. She also points to existing international regulations on human rights, international law and legislation around state responsibility as potential tools to enforce climate action.

“The climate treaties remain very important, they’re just not the only game in town,” she told DW.

Held accountable for historical responsibility

In bringing the case to the court, Vanuatu also asked for clarification on the legal consequences for countries that failed to meet their obligations on slowing their emissions.

Some experts say countries that have emitted most CO2 cumulatively — including the United States, China, Russia, and the European Union — carry the most responsibility for global warming.

“Past emissions matter,” Chowdhury told DW, adding that harm has already been done. “That must be recognized and repaired.”

The request for an Advisory Opinion was brought by the Pacific island Vanuatu. Image: Piroschka Van De Wouw/REUTERS

Poorer countries have long been calling for richer nations to pay for damage caused by extreme weather linked to the emissions that are heating the planet. Many of these less wealthy states are experiencing the worst impacts of climate change, despite having done the least to contribute to the crisis.

The ICJ advisory warned that “adverse impacts and loss and damage will escalate with every increment of global warming”.

It made clear that countries have to meet their climate obligations or potentially see affected countries seek reparations through legal action.

A loss and damage fund was established at UN climate negotiations two years ago in Dubai, but has only received around $700 million in pledges. That is far lower than the hundreds of billions of dollars experts say climate change could cost in damages by 2030.

“At its heart, this case is about accountability. It’s a signal to end the era of empty pledges,” Chowdhury added.

The impact of climate change on human rights

The ICJ advisory opinion is one of three that have been delivered in past months outlining state obligations around climate action.

Earlier this month, the Inter-American Court of Human Rights issued an advisory opinion asserting countries’ obligations to protect citizens’ human rights by ensuring a healthy environment and stable climate.

The opinion also highlighted states’ responsibility in relation to disinformation and misinformation, adding that authorities should not obstruct the population’s access to “reliable, truthful, and complete information” needed to address risks to human rights occurring through the climate emergency.

And in May last year, the International Tribunal for the Law of the Sea was the first to issue its advisory opinion recognizing greenhouse gases as a form of marine pollution.

Although advisory opinions are not legally binding, they hold significant legal weight and moral authority.

Speaking ahead of Wednesday’s ruling, Chowdhury said the advisory opinion could have far-reaching consequences for the November COP30 climate negotiations in Brazil. It could mean “not everything is up for negotiation” because some things have been clearly legally defined.

“We hope very much that this clarity will provide a very clear legal blueprint which would allow states and those most affected on the front lines to hold polluters accountable for climate disruptive conduct and to secure remedy and reparations,” she said.

Edited by: Tamsin Walker