MELTDOWN: Snow caps are melting from Mount Ausangate and other Andean mountains, leaving the local people struggling for water.
CREDIT: ISTOCKPHOTO/REST

MAHUAYANI, Peru—A full moon hangs in the frosty sky as hundreds of dancers file in darkness toward the top of the Sinakara valley high in the Andes. Footsteps crunch frozen tundra, and  dancing shoes step gingerly over ice-covered rivulets. Musicians blow on numb fingers as sunlight tips the hills to the west and creeps up the valley.

High above, ice fields on the eastern peaks remain in shadow.

Suddenly dancers and musicians turn eastward and kneel, baring their heads. A halo rims the tallest crag, and as the sun appears, music bursts from scores of flutes, drums, accordions and saxophones. Moments later the air fills with the sound of running water, as the skin of ice melts, freeing the rivulets.

At more than 15,000 feet above sea level, it is easy to understand why Andean people have long worshiped the elements that allow them to survive in this harsh climate. In the dry season - May to October - rivulets form streams that flow to rivers far below, providing drinking water and keeping alpine pastures alive so livestock can survive until the rains come again.

Backlit by the sun, long columns of men dressed in shaggy black robes stream down the mountainsides. In a test of endurance and devotion, they have spent the night on the glaciers that still cling to the rocks above the valley. Waving banners and surrounded by dancers, they return to the sanctuary of the Señor de Qoyllur Rit'i, the center of a Christian fiesta rooted in a far older Andean devotion.

These men, known as ukukus, whose costumes evoke the Andean spectacled bear, used to hack off huge hunks of ice and haul them down the mountain on their backs. That is now forbidden. They and the tens of thousands of pilgrims who stream up the mountainside every year are worried that the glacier that is central to this ritual is disappearing.

Climate change is forcing a cultural change.   

While governments seek technical solutions to climate-related problems, Quechua-speaking farmers in the Andes are struggling to understand events that are altering their livelihood. Drip irrigation and water reservoirs are only a partial response to a profound change in their relationship with their environment.   

People in the Andes "lead vertical livelihoods," says Jeffrey Bury of the University of California at Santa Cruz. They take advantage of every ecological niche, growing crops in valleys and grazing llamas and alpacas on to bleak mountaintops. But farmers are being squeezed by warmer temperatures that shift crops up mountainsides and the expansion of mountaintop mining that destroys high wetland pastures, Bury says.

Audio slide show: Effects of Climate Change on People in the Andes

Andean peaks are more than scenery; they are protective deities, or apus. For generations, the massive and powerful Mt. Ausangate near the Qoyllur Rit'i sanctuary has been white. Now, it is streaked where snow has melted and bare rock shows.

"The mountains are powerful in a very everyday kind of way. People speak of them, there's a lot of ritual involved with them, and their darkening is very disturbing," says Ben Orlove, an anthropologist at the University of California at Davis, who has studied Andean communities since the 1970s. "There's something very troubling about the glaciers being gone."