Chimborazo

Chimborazo is a stratovolcano located in Ecuador’s Cordillera Occidental range of the Andes. Its last known eruption is thought to have taken place around AD 550. While it is the highest mountain in Ecuador and ranks as the 39th-highest peak in the entire Andes, its summit—at 6,263 meters (20,548 feet) above sea level—is far lower than Mount Everest’s 8,849 meters (29,032 feet). However, because the Earth bulges at the equator, Chimborazo’s summit is the farthest point on the planet’s surface from its center.

The name Chimborazo has several possible origins. In many Quechua dialects, “chimba” (or “chimpa”) means “on the other side,” and “razu” means “ice” or “snow.” Local Quichua speakers say “Chimborazo” is a Hispanicized version of “chimbarazu,” meaning “the snow on the other side.” Another theory combines the Cayapa word “Schingbu” (Women) with the Colorado/Quichua “Razo” (Ice/Snow) to yield “Women of Ice.” A Shuar interpretation holds that “Chimbo” means “Throne of Master/God,” giving “Icethrone of God.” Locals also called the mountain “Urcurazu,” from Quichua “Urcu” (Mountain) plus “Razu,” meaning “Mountain of Ice.” In indigenous mysticism, Chimborazo represents Taita (Father), while neighboring Tungurahua is Mama and Pichincha is Guagua (Child)—hence Taita Chimborazo, Mama Tungurahua, and Guagua Pichincha.

Chimborazo sits in Ecuador’s Chimborazo Province, 150 kilometers (93 miles) south-southwest of Quito. It neighbors the 5,018-meter (16,463-foot) inactive stratovolcano Carihuairazo. Its summit rises about 2,500 meters (8,202 feet) above the surrounding highlands (roughly 3,500 to 4,000 meters, or 11,483 to 13,123 feet), and its base spans about 20 kilometers (12 miles). On clear days, the summit can be seen from Guayaquil, nearly 140 kilometers (87 miles) away. The nearest cities are Riobamba (about 30 kilometers southeast), Ambato (about 30 kilometers northeast), and Guaranda (about 25 kilometers southwest). The mountain is encircled by the Reserva de Producción Faunistica Chimborazo, a protected area that preserves habitat for native Andean camelids such as vicuña, llama, and alpaca. Chimborazo lies at the main end of the Ecuadorian Volcanic Arc, northwest of Riobamba, and is part of the Avenue of Volcanoes, west of the Sanancajas mountain chain. Neighboring peaks include Carihuairazo, Tungurahua, Tulabug, and El Altar; the closest, Carihuairazo, is 5.8 miles (9.3 kilometers) away. Microclimates near the volcano range from desert in the Arenal to humid conditions in the Abraspungo valley.

The summit is covered by glaciers, with some northeastern arms descending to 4,600 meters. These glaciers supply water to populations in Bolívar and Chimborazo provinces. Their ice mass has shrunk over recent decades, partly attributed to ash cover from recent volcanic activity at Tungurahua. Chimborazo has been used in geographical research as a case study for tropical glacier retreat and water-resource vulnerability in the central Ecuadorian Andes. A 2017 study by Jeff La Frenierre and Bryan G. Mark, combining meteorological records, glacier-change analysis, and local observations, found evidence of warming between 1986 and 2011; residents interviewed reported reduced rainfall and lower surface-water availability. This makes the volcano a key site for understanding how high-mountain ice loss can affect communities dependent on Andean water systems. Locals known as Hieleros (from Spanish “hielo” for ice) mine glacial ice to sell in Guaranda and Riambamba markets; historically, ice was transported to coastal towns like Babahoyo and Vinces for cooling.

At 6,263 meters (20,548 feet), Chimborazo is the highest mountain in Ecuador and the highest in the Andes north of Peru, surpassing any more northerly summit in the Americas. Although Mount Everest is higher above sea level, Chimborazo’s summit is widely reported as the farthest point on Earth’s surface from the planet’s center, with Huascarán in Peru a very close second. Because Earth is an oblate spheroid—thicker at the equator than from pole to pole—Chimborazo, located one degree south of the equator, holds this distinction. The Earth’s diameter at the equator is greater than at Everest’s latitude (nearly 28° north), where sea level is also elevated. Despite being 2,585 meters (8,481 feet) lower in elevation above sea level, Chimborazo’s summit is 6,384.4 kilometers (3,967.1 miles) from Earth’s center—2.1 kilometers (1.3 miles) farther than Everest’s summit (6,382.3 kilometers, or 3,965.8 miles). However, by height above sea level, it is not the highest peak in the Andes. Centrifugal force from Earth’s rotation and distance from the center slightly reduce gravity near the equator; Chimborazo’s summit has about one percent less gravity than the point with the highest gravitational force. Yet, due to its height above surrounding terrain and local gravity anomalies, Huascarán’s summit is the place on Earth with the smallest gravitational force.

Geologically, Chimborazo is an ice-capped inactive volcano. It is a double volcano, with one volcanic edifice atop another, and shows four summits: Whymper.