Shallow ground temperature measurements on the highest volcano on Earth, Mt. Ojos del Salado, Arid Andes, Chile

AbstractMt. Ojos del Salado (6893 m a.s.l.) lies within the Andean Arid Diagonal, on the Chilean–Argentinean border. Due to the extremely arid climate, surface ice is not widespread on Mt. Ojos del Salado and at similar high‐altitude massifs in the region, although ice‐bearing permafrost might be present. However, the thermal regime of the ground is relatively unknown in the region, especially outside of rock glaciers at high elevations north of 30°S. To study ground thermal regimes, in‐situ shallow ground temperature and snow coverage from satellite imagery have been surveyed for four years (2012–2016) at six sites between the elevations of 4200–6893 m a.s.l. on Mt. Ojos del Salado (27°07′S, 68°32′W). According to the ground temperature and snow coverage data at the six monitoring sites, the presence of permafrost is unlikely below 4550 m a.s.l. but likely above 5250 m a.s.l. on Mt. Ojos del Salado. In addition, the active layer becomes extremely thin around 6750 m a.s.l.