Chacaltaya ( Mollo language for "''bridge of winds''" or "''winds meeting point''", Aymara for "cold road") is a mountain in the Cordillera Real, one of the

mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have aris ...

s of the Cordillera Oriental, itself a range of the

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

. Its elevation is . Chacaltaya's

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

— which was as old as 18,000 years — had an area of in 1940, which had been reduced to in 2007 and was completely gone by 2009. Half of the meltdown, as measured by volume, took place before 1980. The final meltdown after 1980, due to missing precipitation and the warm phase of El Niño, resulted in the glacier's disappearance in 2009. The glacier was located about from

La Paz La Paz, officially Nuestra Señora de La Paz (Aymara language, Aymara: Chuqi Yapu ), is the seat of government of the Bolivia, Plurinational State of Bolivia. With 755,732 residents as of 2024, La Paz is the List of Bolivian cities by populati ...

, near

Huayna Potosí Huayna Potosí is a mountain in Bolivia, located near El Alto and about 25 km north of La Paz in the Cordillera Real (Bolivia), Cordillera Real. Huayna Potosí is the closest high mountain to La Paz. Surrounded by high mountains, it is ...

mountain.

Ski area

The glacier on Chacaltaya served as Bolivia's only

ski resort A ski resort is a resort developed for skiing, snowboarding, and other winter sports. In Europe, most ski resorts are towns or villages in or adjacent to a ski area–a mountainous area with pistes (ski trails) and a ski lift system. In North Am ...

. It was the world's highest lift-served ski area and the northernmost in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. The rope tow, the first in South America, was built in 1939 using an automobile engine; it was housed in the site's original clapboard lodge, and is now inoperable. The road to the base of the drop is reached by a narrow road, also built in the 1930s. Traditionally, due to the extreme cold weather, the lift operated exclusively on weekends from November to March. Since 2009, skiing is restricted to a stretch that sometimes receives sufficient snowfall for a run during the winter. The mountain is also popular with amateur mountaineers, as the road stops only from the summit.

Guinness World Records ''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a British reference book published annually, list ...

considers the ski resort restaurant to be the highest restaurant in the world.

Retreat of Chacaltaya glacier

Scientists at the Mount Chacaltaya Laboratory started measuring the Chacaltaya glacier in the 1990s. Predicted at that time to survive until 2015, the glacier melted at a faster rate than expected. By 2009, it had been reduced to a few small patches of ice and snow near the top of the mountain. (Diagram and photos of development) Many Bolivians on the

Altiplano The Altiplano (Spanish language, Spanish for "high plain"), Collao (Quechuan languages, Quechua and Aymara language, Aymara: Qullaw, meaning "place of the Qulla people, Qulla") or Andean Plateau, in west-central South America, is the most extens ...

and in two of Bolivia's main cities — La Paz and El Alto — depend on melt water from Andean glaciers for part of their water supply during the dry season. The

World Bank The World Bank is an international financial institution that provides loans and Grant (money), grants to the governments of Least developed countries, low- and Developing country, middle-income countries for the purposes of economic development ...

has warned that many glaciers in the

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

portion of the Andes are expected to disappear within 20 years. This will threaten the water supplies of nearly 80 million people as well as the future generation of

hydropower Hydropower (from Ancient Greek -, "water"), also known as water power or water energy, is the use of falling or fast-running water to Electricity generation, produce electricity or to power machines. This is achieved by energy transformation, ...

. Bolivia,

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

, and

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

depend on hydropower for about half their electricity.

Observatory

Located at , the Mount Chacaltaya Laboratory began as a weather station in 1942. It is an important site for

gamma ray A gamma ray, also known as gamma radiation (symbol ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists o ...

research and was the site in the 1940s of the first observations of

pions In particle physics, a pion (, ) or pi meson, denoted with the Greek letter pi (), is any of three subatomic particles: , , and . Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the lightest mesons and, mo ...

. The Chacaltaya (Astrophysical) Observatory belongs to the Universidad Mayor de San Andrés and it is operated in collaboration with other universities worldwide. It hosts a cosmic ray research group, and since 2011 the Chacaltaya Global Atmosphere Watch (GAW) station. The GAW station is one of the few monitoring sites of Essential Climate Variables (meteorological variables,

aerosols An aerosol is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be generated from natural or human causes. The term ''aerosol'' commonly refers to the mixture of particulates in air, and not to t ...

, and

greenhouse gases Greenhouse gases (GHGs) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. Unlike other gases, greenhouse gases absorb the radiations that a planet emits, resulting in the greenhouse effect. T ...

) in the Southern Hemisphere.

Climate

References

External links