The climate plants experience

Abstract

Walking across an alpine fell field on a bright day, the mountaineer my find it still chilly and windy, and “dry” air may desiccate the skin. A nearby meteorological station with all its weather masts confirms: +4°C air temperature, 5 ms⁻¹ wind speed, 40% relative humidity. While our mountaineer experiences the harsh life in the mountains, the world looks different for those who stay close to ground. Micrometeorological research in alpine vegetation has shown that, under the conditions described above, the climate within a compact leaf canopy 1–2 cm above the ground, for instance among cushion plants, may be +27°C, 98% relative humidity and no convective air movement — life in a humid tropical forest? Seed beds of alpine plants on dark humic soils exposed to full sunlight have been shown to heat up to temperatures of around 80°C (Alps of Tirol, Turner 1958b; Australian Snowy Mountains, Körner and Cochrane 1983).