CHACALTAYA, Bolivia — If anyone needs a reminder of the on-the-ground impacts of global climate change, come to the Andes mountains in Bolivia. At 17,388 feet above sea level, Chacaltaya, an 18,000 year-old glacier that delighted thousands of visitors for decades, is gone, completely melted away as of some sad, undetermined moment early this year.
''Chacaltaya has disappeared. It no longer exists,'' said Dr. Edson Ramirez, head of an international team of scientists that has studied the glacier since 1991.
Chacaltaya (the name in Aymara means ''cold road'') began melting in the mid-1980s. Ramirez, the assistant director of the Institute of Hydraulics and Hydrology at the Universidad Mayor de San Andres in nearby La Paz, documented its disappearance in March.
Approximately 35 miles from La Paz, it takes an hour and a half to drive the gravel and rock road up tortuous switchbacks to the top of the mountain of the same name. Visitors on a clear day -- and there are many such days -- can see the Bolivian highland plain, or altiplano, thousands of feet below, and the nearby Huayna Potosi and Illimani mountains, part of the Cordillera Real de los Andes.
AN EARLY DEATH
Ten years ago Ramirez and his team of researchers concluded that the glacier would survive until 2015. But the rate of thaw increased threefold in the last decade, according to their studies. He believes the disappearance of Chacaltaya is an indication of the potent effects at higher elevations of the interaction of greenhouse gas accumulation and an increase in average global temperatures.
And he thinks other glaciers in the region also may be melting at a rate faster than previously known. Illimani, the colossal 21,200-foot mountain that looms over the city of La Paz and has served as the backdrop for postcard-perfect pictures since film was invented, is the home to several glaciers. They likely will melt completely within 30 years, he said.
''It's very probable that other glaciers are disappearing faster than we thought,'' he said. Researchers fear that Chacaltaya's fate will be shared by other glaciers in other areas of Bolivia, and in Peru and Ecuador as well, he said.
In May, the members of Ramirez's research team will gather here to honor the fallen glacier and to commemorate the end of 18 years of work.
Chacaltaya became well-known long before it started melting. For decades it was declared, and aggressively marketed, as ``the highest ski run in the world.''
Despite the melting of the glacier, today a handful of hard-core alpinistas and the occasional adventure tourist still schlep their skis and poles over the summit a few hundred yards from where the glacier used to be. On a lucky day, when a little snow has fallen just below the stony ridge, they can ski for about 600 feet. Then they walk back.
THE SKI LODGE
''Very few come to ski now,'' laments Alfredo Martinez, 73, who is one of the founders of the Club Andino de Bolivia, based in La Paz. A lifelong mountaineer, Martinez and a small cadre of mostly young followers keep the ski lodge open, serving tea and soup and burning old wooden boards from a nearby building in the fireplace for warmth. They charge visitors 15 bolivianos, the equivalent of $2.10, for a clean-up and maintenance fund.
In the good old days, when every tour agency and guide book heralded Chacaltaya's unique altitudinal fame, the Club Andino organized ski competitions and stored the equipment of dozens of its members in the lodge. A large stone-and-wood building housed a winch-and-cable tow operation that dragged skiers to the top of the glacier. The descent was often heart-stopping, and if the skiers didn't stop in time they could end up on the rocks below the snow-topped glacier.
But it's not the end of alpine skiing at Chacaltaya that worries researcher Ramirez, but the death of the glacier and what that means for the people of the Andean cordillera. On the western, mostly arid side of the Andes, millions of people depend on rain, snow run-off and melting glaciers like Chacaltaya, Illimani and Huayna Potosifor their water.
There's another problem, too. Not only are the glaciers melting, but less rain seems to be falling in the Andes, according to recent studies. The big rain-carrying monsoons drifting west from the Amazon basin have declined in size and intensity, another indication of major climactic changes, Ramirez said.
This year, for the first time, the amount of water flowing out of reservoirs serving nearly 2.5 million people in La Paz and its adjacent city, El Alto, will exceed the amount of water flowing into them. This eventually will become a major political issue for leaders in La Paz and El Alto, he said.
To Juan Velazquez, who grew up just over the mountain from Chacaltaya in the now-abandoned mining town Mulluni, and later moved with his family to La Paz, the defunct glacier means less income. As a taxi driver, he can earn the equivalent of 50 U.S. dollars driving tourists from La Paz to the glacier and back. That's the equivalent of a month's wages for some in this impoverished land.
But the loss of the glacier is the saddest part for him, not the lost wages.
As a child, he and his playmates would use paint to darken under their eyes, just like they saw in American movies, then journey up to Chacaltaya to play in fresh snow atop the glacier.
''It's a tragedy,'' he said. ``It's as if someone had died.''