The role of snow melting upon landslides in the central Argentinean Andes

摘要

This paper focuses on the historical range of variability of landslide activity and its relation to climate in the Aconcagua Park, Argentina. Landslide frequency data are obtained through historic compilation, including the review of more than 85 data sources and personal interviews with members of the local community. Based on these records, the study analyzes major landslide triggering mechanisms and evaluates the role of climate. Slope instability in Aconcagua Park appears to be mainly forced by the melting of snow accumulated during the winter season, which in turn promotes soil saturation and landslide occurrence the following spring-summer (December-February). This finding is supported by a strong correlation between landslides and stream flows of Andean rivers. These peaks occur during warmer seasons, fed by snow and ice-glacier melting. In contrast, the correlation between landslide frequency and precipitation (diary/accumulative/monthly/annual) is less certain; and the relationship of landslide to temperature records (mean annual temperature/mean temperature during November-February period) is weak.