The New York Times, Nov. 24, 2002
CHACALTAYA MOUNTAIN, Bolivia — From the top of this snow-capped peak 17,400 feet up, the surrounding Royal Range looks as healthy as ever: deep, glittering snow and a thick covering of glaciers as far as the eye can see.
But as Eulalio Gonzales, a veteran mountain guide, surveyed from the craggy peak overlooking Bolivia's windswept highlands, all he saw were remnants, fading and shrinking fast.
This mountain's glacier, boasting the world's highest ski slope, has been melting so steadily that scientists predict its demise in a decade. The Zongo glacier on the nearby mountain of Huayna Potosi is retreating by 10 yards a year.
On a third peak, the 18,000-foot Condoriri, the glacier that supplies the largest reservoir in the Bolivian highlands is shriveling so fast that scientists fear a scarcity of drinking water in the decades to come.
"Each day we are more and more worried because these are the waters we drink from, but there is retreat all around," said Mr. Gonzales, peering through sunglasses under a bright sun and springlike climate. "This was so much different before — there was just much more snow and ice."
In a phenomenon scientists here and abroad call a calamity in the making, the glaciers of the central Andes are vanishing because of global warming driven at least in part by pollution.
Their disappearance, scientists now say, is nearly unavoidable and could lead to water shortages in places like Bolivia and Peru that depend on glaciers and the rain and snow that fall on the mountains for water for drinking, irrigating fields and generating electricity.
"For our future, it is worrisome because we may not have enough water," said Ronaldo Maldonado, the government's chief meteorologist. "Demand could grow, but supply could be less. If this happens we could be in a tremendous crisis."
Shrinking glaciers are a worldwide phenomenon, with great slices of snow and ice disappearing every year from the Austrian Alps to Glacier National Park in Montana. But the glaciers of the tropics — the vast majority in the Andes, stretching from Venezuela to Bolivia — are losing ground the fastest.
They are smaller to begin with and are located in a region that is more sensitive to climate change — and the climate has changed.
In Bolivia the temperature rose by 1 degree centigrade in the last century, mirroring the rise in some other parts of the world, said Robert Gallaire, a hydrologist with the Institute of Research for Development, a French scientific organization studying glaciers here.
At the same time, less rain and snow are falling in the area around La Paz, with the average annual rainfall dropping to 17.88 inches in the 1990's from 22.4 inches in the 1980's, according to measurements at Milluni Lagoon at the foot of Huayna Potosi.
Scientists attribute the unseasonably dry years to El Niño, a weather phenomenon generated by warm Pacific currents off the South American coast that has struck numerous times in the last two decades.
The changes are already being noticed by the people who live in the mountains, raising anxieties. "It is worrisome," said Angel Quisverte, 55, a potato farmer who lives on the north side of Zongo, "because if there are no snows, then there is no life."
He said he feared for the future of agriculture in the green valley where he lives. "All the mountains here had snows before, but now it's melting," he said. "Ten years ago I started to see it — and every year it keeps going down and down."
The climatic changes have been disastrous throughout the region for mountain glaciers, which have been vanishing at a particularly rapid pace in recent years.
At the huge Quelccaya Ice Cap, which stretches across Peru, the largest glacier, Qori Kalis, is retreating at a rate 44 times as fast today as it was from 1963 to 1978, when American scientists determined it was melting by about four yards a year.
Glaciers in Venezuela are nearly extinct, and in Bolivia the mass of glaciers and snowcaps has shrunk by 60 percent since 1978, according to government estimates.
In all, according to the Byrd Polar Research Center at Ohio State University, Andean glaciers have retreated by as much as 25 percent in the last 30 years.
"They cannot resist," said Mr. Gallaire, the hydrologist, speaking in his office in La Paz. "These glaciers are much more fragile than in the north. It is the great problem of the tropical glaciers."
Government officials and scientists believe that if the glaciers keep melting at this rapid pace, a serious water shortage could loom for Bolivia, which lacks the resources or know-how to adapt to the significant climate changes it has done little to generate. Most scientists blame industrialized nations, like the United States, the world's largest producer of heat-trapping gases.
Government officials said the country had not planned for the effects of continued global warming. No in-depth studies have been conducted, and no plans for building or improving reservoirs and other infrastructure are even on the drawing board.
"The problem is we are using reserves that are being reduced," Mr. Gallaire said. "So we have to ask, what will happen in 50 years? Fifty years, you know, is tomorrow."
The most pressing concern, government officials said, is the possible shortage of water for the 1.5 million people of La Paz and the adjacent city of El Alto. Over the next decade, water use in the region is expected to increase by 20 percent.
Scientists say that without the glaciers the region's natural water cycle will be disrupted. Glaciers release water in dry seasons and collect it in rainy ones.
"It's a natural dam," said Lonnie Thompson, a research scientist at the Byrd Center who has studied Andean glaciers closely. "Some people refer to these glaciers as the world's water towers, and once they're dry, you lose that water."
For now, at Aguas de Illimani, the French company that runs La Paz's water supply, the situation is not seen as critical. The president, Roberto Bianchi, asserted that the company depended mostly on rainwater for its supplies.
But scientists said that glacial melt contributed, too, and Mr. Bianchi acknowledged that "if, as a consequence of a possible disappearance of glaciers, the routine of precipitation is altered, we are exposed."
Up in the mountains, what is happening is no secret to farmers, shepherds and the hardy mountain guides of the Bolivian Andean Club. They have seen the spectacular ice caves of Charquini mountain, conical ice sculptures formed by fierce winds, disappear. They have also seen the glaciers give up the ghosts of the past, like the wrecks of airplanes that had disappeared into glaciers decades ago.
In a country where half the population is indigenous and reveres the mountains as Achachilas, or givers of life, the changes are seen with deep melancholy.
"People have to ask for life from the mountain," explained José Huanca, 32, who lives next to the Tuni reservoir at the base of the Condoriri glacier. "They are the owners of the land, of the animals. But I think the Achachilas are leaving."