Global solar radiation, soil temperature and permafrost in the Central Andes, Argentina: A progress report

Abstract

Abstract During various expeditions to the High Andes of Argentina at latitudes 30º and 33º south, extensive geomorphological investigations have been carried out. The subtropical semiarid climate is characterized by intense global radiation with peaks of more than 1400 W/m 2 and daily sums of >39 MJ/m 2 . The daily amplitudes of the soil temperatures (≤25 cm depth) correlate with incoming radiation. Diurnal ranges of soil surface temperature (1 cm) usually exceed 45ºC, with maximum values of 55ºC at 4150 m a.s.l. Active rock glaciers exist above 4000 m a.s.l. and the thickness of the active layer varies from 1.4 to 2.5 m between 4000 and 4700 m a.s.l. Periglacial features (rock glaciers, thermokarst, gelifluction, etc.) are widespread. They are used as edaphic indicators for the lower limit of discontinuous permafrost, which is thought to be at an elevation of 4000 ± 200 m a.s.l.