Penitente (snow formation) in the context of "Mount Rainier"

The Dry Andes (Spanish: Andes áridos) is a climatic and glaciological subregion of the Andes. Together with the Wet Andes it is one of the two subregions of the Argentine and Chilean Andes.

The Dry Andes runs from the Atacama Desert in northern Chile and Northwest Argentina south to a latitude of 35°S in Chile. In Argentina the Dry Andes reaches 40°S due to the leeward effect of the Andes. According to Luis Lliboutrythe Dry Andes can be defined by the distribution of penitentes. The southernmost well-developed penitentes are found on Lanín Volcano.

Louis Lliboutry (1922–2007), born in Spain, was a French glaciologist, geophysicist, university professor and mountaineer. While in Chile in the early 1950s, he analysed and explained the formation of snow penitents in the Andes, which marked his first contribution to glaciology. He founded in Grenoble in 1958 the Laboratoire de glaciologie et géophysique de l'environnement [fr] and headed it for 25 years; he also set up at that period a pioneering syllabus in geophysics. His contributions to mechanics of viscous media (such as ice and the Earth's mantle) and to geodynamics are internationally acknowledged.