Natural regions of Chile for reference purposes. These natural regions are ordered from north to south and reduced to five natural regions: Each has its own characteristic vegetation, fauna, climate, and, despite the omnipresence of both the Andes and the Pacific, its own distinct topography. Most of the region is covered by the Atacama Desert and has a dry arid climate. The coast range has peaks over 2000 m and ends in cliffs in the coast. There are large salt flats in the Intermediate depression and the Andes. Norte Grande has Chile's highest mountains including Ojos del Salado (6,891 m) but host also the
Ojos del Salado reports indicate the absence of glaciers on Ojos del Salado. Permafrost exists on the mountain and its melting nourishes several lakes; one lake fed by a creek lies at altitude. Ojos del Salado is an active volcano, but the question of whether it should be considered "currently" (or "historically") active is arguable. According to the Smithsonian Institution's Global Volcanism Program, the most recent known eruption was about 1,300 years ago, with a large margin of uncertainty. However, there is also some evidence for a minor ash emission in 1993, which would definitely qualify the volcano as historically active. The presence