With their lawsuit before the ECtHR, the climate seniors want to ensure that Switzerland is forced to do more climate protection by court order. In her view, her country is not doing enough to protect the climate and is thus violating human rights. The court is now to examine whether and how human rights oblige individual states to stop climate change. A verdict is not expected for several months.

At the beginning of the proceedings, many climate seniors traveled to the court in Strasbourg. The negotiation room was packed, and several hundred people crowded in front of it. "We've been fighting for this for years," Bruna Molinari, 81, told AFP. "We hope that the court will agree with us and that Switzerland must do more than it has done so far."

"We are confident that we can make history with this case and get Switzerland to do more climate protection," said Anne Mahrer, co-president of the Swiss climate seniors. They are supported in their lawsuit by Greenpeace. "Today has the potential to go down in history as a milestone in the global fight against the climate catastrophe that is becoming increasingly apparent," said the environmental protection organization.

Greenpeace emphasized that for the first time in its history, the ECtHR was dealing with the content of a procedure with the effects of climate change on human rights. The procedure will clarify "whether and to what extent a country like Switzerland must reduce its greenhouse gas emissions more to protect human rights".

The court also wanted to start hearing a climate lawsuit against France on Wednesday. Plaintiff is a former mayor of a town in northern France threatened by sea level rise. In a third climate lawsuit before the ECtHR, which will probably not be heard until after the summer, several Portuguese have appealed to the court about the environmentally harmful greenhouse gas emissions of 32 Council of Europe states.