Glacialismo recente e variazioni climatiche nelle Alpi Aurine e Pusteresi

Recent Glacier Behaviour and Climatic Factors in the Aurine and Pusteresi Alps (Eastern Alps)

Abstract

Measurements of the snout variations of the Aurine and Pusteresi glaciers (Noriche Alps) are available from 1929; they indicate a general retreat interrupted by a short advance between 1977 and 1983. The climatic parameters recorded starting from the 20’s at Terme di Brennero (1,320 m) allow some evaluation on the mechanisms that control the snout variations and their response time. The advance seems due to the concomitance between colder temperatures in summer and a higher amount of precipitation in winter. The retreat of the 30's seems to be governed by a different climatic trend with respect to the one that governs the present regression. The response time, which results for some glaciers within 5 years for temperature and at least the double for precipitation, is directly proportional to the size of the glacier. The analysis of glacier behaviour in the area examined allows to exclude the exsistence of other advances apart from the measured one and makes it possible to extrapolate the known snout variations to the periods lacking measures.