Snow in the Picos de Europa : geomorphological and environmental implications

Abstract

The Picos de Europa massif is the maximun exponent of the Atlantic High Mountain of SW Europe. The present day climate derive initially from its volume and altitude, with peaks of around 2.700 m, and from its geographical location. Its proximity to the Cantabrian Sea, only 20 km away, defines it as an oceanic high mountain massif with wet winters (2.500-3.000 mm/year). Its climate is characterised by warmer temperatures than other Iberian high mountain areas (Pyrenees and Sierra Nevada), and the distribution of snow in time and space, highly abundant, but unstable (wet snow), is a fundamental geoecological factor in the massif. In this work we have analysed the distribution and dynamic of the snow covering depends on factors such as altitude, topography, orientation, exposure and wind redistribution processes. At 1500 m the duration of the snow cover is 6/7 months, whereas at over 2000 m, a duration of around 8 months is estimated, though this is highly variable depending on several factors. The dominant process on the high mountain of Picos de Europa is the nivation, related to karst, solifluction and gelifraction. The duration and distribution of the snow cover dictates the seasonal variations of the meteorization (thermal regulation of the freeze/thaw cycles on the ground), the availability of water on the slopes and the sediment transport. The nivation also is an effective morphological agent.