Abstract
Climate change is already affecting high mountain regions, such as the European Alps. Those regions will be confronted with a significant rise of temperatures above the global average, and more and heavier rain events, also during wintertime. The system response to the coincidence of rain, snow, and possibly frozen soil depends on the almost infinite number of possible combinations of thermo-hydraulic states of the involved phases. Landslides, snow avalanches, debris flows, or extensive surface runoff are just a few of the possible hazardous outcomes. With rising temperatures and increased precipitation, those hazardous outcomes are expected to occur even more frequently in the future, requiring a better understanding of those coupled processes for hazard mitigation strategies. The macroscopic phenomena are controlled by porescale processes, such as water freezing and ice grains blocking pores, which are only barely understood. The strong coupling between thermal state and hydraulic parameters, the possible phase change, and material heterogeneity pose great challenges for investigation. This work provides an overview of documented hazard events regarding rain, snow, and possibly frozen soil. The current state in theoretical and experimental research is presented before several knowledge gaps are derived and possible techniques to address those gaps are discussed.
Highlights
Climate change already affects Alpine Europe as changed weather conditions have arrived in local spots and confronted communities with increased precipitation patterns or frequent flood events [1,2]
This work provides an overview of documented hazard events regarding rain, snow, and possibly frozen soil
It is predicted that temperatures increase considerably more in mountain areas compared to the global average [8]. This will induce more and heavier rain events [4], in particular, during the winter months [9,10], as well as diminish the ice and snow coverage, melting alpine glaciers, thaw permafrost grounds, and initiate more rain-on-snow events [3,8,11,12]
Summary
Climate change already affects Alpine Europe as changed weather conditions have arrived in local spots and confronted communities with increased precipitation patterns or frequent flood events [1,2]. It is predicted that temperatures increase considerably more in mountain areas compared to the global average [8] This will induce more and heavier rain events [4], in particular, during the winter months [9,10], as well as diminish the ice and snow coverage, melting alpine glaciers, thaw permafrost grounds, and initiate more rain-on-snow events (liquid precipitation falls on pre-existing snowpack) [3,8,11,12]. Documented Hazard Events Containing Precipitation, Snow, and Frozen Soil Numerous serious natural hazard events occurred in the European Alps in recent years [3] Some of these events are dedicated to the seasonal transition between winter and spring when a combination of rainfall and snow melting coincides or occur towards the end of the summer and the early fall [27,28,29]. This will challenge theoretical approaches, experimental investigations, and numerical modelling
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
