We monitored the climate in high-elevation páramo of Antisana (Ecuador) to analyze its diurnal and annual variation. We established two climatic stations on the western (leeward) side of the mountain at 4280 m and 4600 m, and two stations on the north-eastern (windward) side at 4120 m and 4430 m. The western side of Antisana received 35% more solar radiation than the north-eastern side. Night frosts were frequent on the western side whereas high humidity and cloudiness on the north-eastern side reduced the number of frost nights. Frosts were rather mild and of short duration; the minimum temperature recorded was –6.1°C and most frost periods lasted less than four hours. Freezing temperatures were most frequent during periods of reduced humidity. Temperature lapse rates calculated for the 300 m elevational gradient were 0.44 K/100 m and 0.55 K/100 m for the western and north-eastern sides, respectively. Potential evapotranspiration values suggested that water was in surplus year-round on the north-eastern side of Antisana, but its availability was limited during drier periods on the western side.
Sklenář et al. (Thu,) studied this question.