An integrated approach to investigate climate-driven rockfall occurrence in high alpine slopes: the Bessanese glacial basin, Western Italian Alps  

作　　者：VIANI Cristina CHIARLE Marta PARANUNZIO Roberta MERLONE Andrea MUSACCHIO Chiara COPPA Graziano NIGRELLI Guido 

机构地区：[1]Department of Earth Sciences,University of Torino,10125 Torino,Italy [2]Research Institute for Geo-Hydrological Protection,Italian National Research Council,10135 Torino,Italy [3]Institute of Atmospheric Sciences and Climate,Italian National Research Council,10133 Torino,Italy [4]National Institute of Metrological Research,10135 Torino,Italy

出　　处：《Journal of Mountain Science》2020年第11期2591-2610,共20页山地科学学报（英文）

基　　金：the framework of the RiST Project,co-financed by“Fondazione Cassa di Risparmio di Torino”and by MeteoMet Project。

摘　　要：Rockfalls are one of the most common instability processes in high mountains.They represent a relevant issue,both for the risks they represent for(infra)structures and frequentation,and for their potential role as terrestrial indicators of climate change.This study aims to contribute to the growing topic of the relationship between climate change and slope instability at the basin scale.The selected study area is the Bessanese glacial basin(Western Italian Alps)which,since 2016,has been specifically equipped,monitored and investigated for this purpose.In order to provide a broader context for the interpretation of the recent rockfall events and associated climate conditions,a cross-temporal and integrated approach has been adopted.For this purpose,geomorphological investigations(last 100 years),local climate(last 30 years)and near-surface rock/air temperatures analyses,have been carried out.First research outcomes show that rockfalls occurred in two different geomorphological positions:on rock slopes in permafrost condition,facing from NW to NE and/or along the glacier margins,on rock slopes uncovered by the ice in the last decades.Seasonal thaw of the active layer and/or glacier debutressing can be deemed responsible for slope failure preparation.With regard to timing,almost all dated rock falls occurred in summer.For the July events,initiation may have been caused by a combination of rapid snow melt and enhanced seasonal thaw of the active layer due to anomalous high temperatures,and rainfall.August events are,instead,associated with a significant positive temperature anomaly on the quarterly scale,and they can be ascribed to the rapid and/or in depth thaw of the permafrost active layer.According to our findings,we can expect that in the Bessanese glacierized basin,as in similar high mountain areas,climate change will cause an increase of slope instability in the future.To fasten knowledge deepening,we highlight the need for a growth of a network of high elevation experimental sites at the basin scale,and the d

关 键 词：ROCKFALLS Climate change Air and rock temperature Periglacial environment Western Italian Alps 

分 类 号：P467[天文地球—大气科学及气象学] P642.2