Above 5,600 metres (18,400 ft), Sajama is extensively glaciated.
It is among the southernmost mountains in the region with significant glaciers; farther south the atmosphere is too dry to permit the development of glaciers.
Two ice cores were taken in 1997 from the summit area after a preceding religious ceremony, as the local Aymara people feared that the mountain deities would be angered by the drilling otherwise.
Rock glaciers also occur above the zero degree isotherm above 4,800 metres (15,700 ft), such as on lateral peaks.

Sajama and neighbouring mountains featured much larger glaciers in the past.
The history of glaciation on Sajama in general is poorly known, but it appears that the outermost glacial features originated during the late last glacial maximum and the intermediary features during the Middle Holocene which is usually considered to be a warm and dry period in the region.
Above 5,600 metres (18,400 ft), Sajama is extensively glaciated. It is among the southernmost mountains in the region with significant glaciers; farther south the atmosphere is too dry to permit the development of glaciers. Two ice cores were taken in 1997 from the summit area after a preceding religious ceremony, as the local Aymara people feared that the mountain deities would be angered by the drilling otherwise. Rock glaciers also occur above the zero degree isotherm above 4,800 metres (15,700 ft), such as on lateral peaks.
Sajama and neighbouring mountains featured much larger glaciers in the past. The history of glaciation on Sajama in general is poorly known, but it appears that the outermost glacial features originated during the late last glacial maximum and the intermediary features during the Middle Holocene which is usually considered to be a warm and dry period in the region.
Nevado Sajama