A 130-year history of avalanche risk in the Fagaras Mountains, Romanian Carpathians deduced from interference with human activities

Snow avalanches are a denudational process and natural hazard that can severely damage tourist infrastructure, roads and forests and lead to injury and loss of life. Political and socio-economic changes in mountain landscapes also affect avalanche activity. This study was carried out in the Făgăraş Mountains, a representative mountain unit in the Southern-Romanian Carpathians, which is dominated by glacial and periglacial relief, high altitudes, high snow cover thickness, snow persistence of about 8-9 months per year and high occurrence of avalanche hazards.

Our analysis of the location, spatial extent and number of avalanche events was based on extensive documentation using old photographs, maps, papers and statistics from Mountain Rescuer Public Services databases. We also used dendrogeomorphological data with a 130-year chronology, from which we extracted the frequency, magnitude and spatial extent, satellite images and event simulations using the RAMMS avalanche module in the most affected area of the Fagaras Mountains, the Balea-Capra glacier sector. The study data were collected between 1880 and 2020, in three different periods, each with political and socio-economic peculiarities: the Romanian Kingdom Period (1880-1945), the Communist Period (1946-1989) and the Post-Communist Period (1990-present). In the first period, the tourist infrastructure was modest with no tourist traffic and the avalanche danger was not recognized. Only three avalanche events with human casualties were recorded. In the communist period 23 avalanche events were recorded. In the post-communist period, 75 avalanche events were recorded. Avalanche activity has strongly interfered with the emergence of new elements of tourist infrastructure such as huts, alpine refuges and the Transfăgărășan highway but also with the increasing exposure of tourists especially in the last 20 years. This is why the Făgăraş Mountains are a real avalanche hot spot in the Romanian Carpathians, accounting for 51.2% of fatalities and 57.4% of injuries/burials.

Studies carried out in the Romanian Carpathians have shown that climate warming is more evident between 1,000 and 1,500 m than at higher altitudes where most avalanches have been recorded. In this context, it is difficult to determine that the frequency and spatial extent of avalanches is determined by global change.