The soft murmur of water trickling from a glacier in the Peruvian Andes into the pale blue lake below is broken by the roar of a chunk of ice breaking off.
Saul Luciano Lliuya, who grew up in these mountains, has spent his whole life watching climate change break the glaciers apart.
Now the 34-year-old Peruvian farmer and mountain guide is suing one of Europe's largest energy companies, RWE of Germany, for what he says is its role in causing global warming—and putting his hometown and his farm at risk.
Luciano looks out his window, which boasts a view of Churup, a 5,400-meter (17,700-foot) peak.
He still remembers when it was covered in snow. Today its summit looks like the head of a bald old man, sparsely covered with tufts of white hair.
"It's a shame the glaciers aren't the same anymore. We're losing them to global warming," Luciano told AFP.
"Someone caused this, and those people have to be held responsible. It's not right to remain silent. The world belongs to all of us, not just the polluters."
Luciano lives with his wife and two kids, farming potatoes, corn, quinoa, barley and wheat in the northern region of Ancash as his family has done for generations.
The mountains that line the horizon are part of the Huascaran National Park, a UNESCO World Heritage Site that has lost 30 percent of its snow cover in the past four decades, according to the Peruvian government.
Luciano blames carbon-emitting industries for that.
A year ago, at a United Nations climate conference in Peru—the precursor to high-stakes talks currently being held in Paris—he met up with activists from the German environmental group Germanwatch, who helped him come up with a novel answer to the problem.
With Germanwatch's help, Luciano is suing RWE, Germany's number two energy producer and what the environmental group calls the "single-greatest CO2 emitter in Europe."
The 20,000 euro question
Germanwatch announced the lawsuit late last month. RWE did not immediately respond, telling AFP it had only learned of the case through the media.
Luciano is seeking a relatively modest 20,000 euros in the German courts—his calculation of RWE's rightful share in the cost of protecting his community from floods caused by melting snow and glaciers.
It is a creative approach to dealing with the question of what economists call "externalities," the consequences of an economic activity experienced by unrelated third parties.
Germanwatch said this is the first time a private individual affected by climate change has sued a company for damages.
Luciano's lawsuit also highlights the tough questions besetting the negotiations in Paris, where there are deep divisions between wealthy countries that developed their economies for more than a century with little concern for pollution and poor countries demanding financial help to do it more sustainably.
It remains to be seen what the courts will make of Luciano's lawsuit.
What is clear is that the melting of the glaciers is creating new lakes and raising the water level in existing ones, putting communities like Luciano's at risk.
The volume of water in the Palcacocha lake is 34 times higher today than in 1970.
The US Agency for International Development (USAID) said in a report last year that the lake is so swollen it has become a permanent threat.
The lake's last major flood was in 1941, when it burst its shores and killed 5,000 people in the regional capital, Huaraz—today a city of 100,000 people.
Luciano wants RWE to help pay for a series of projects to prevent floods, including building a dam.
"This is a precedent," said Germanwatch lawyer Roda Verheyen.
"RWE releases significant emissions, principally through its coal-fired power plants, which makes global temperatures rise, causes glaciers to melt and leads to an acute threat to my client's property. We request that the court declare RWE liable."
Climate change tourism
Global warming has forced the government to come up with a new tourism concept at nearby Pastoruri mountain, which had alpine ski trails until the early 2000s but now has barely any snow.
"We launched a new project last year: Pastoruri, the climate change tour," said Ricardo Gomez, head of the national park.
The day-long hike takes visitors to seven stops where they can see melting glaciers, swelling lakes and disappearing snow cover.
The 720 square kilometers (280 square miles) of glaciers that covered the national park in the 1970s have been reduced to 527, according to park officials.
At that rate, those below 4,500 meters of altitude risk disappearing in the next 25 years, they warn.
"The most immediate fear is that the snow caps will disappear, and with them our fresh water," said Luciano.
"That would be a catastrophe. And when the rivers fed by the glacial melt swell, that problem is going to be felt all the way to the coast."
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