Item: THE DESTRUCTIVE POTENTIAL OF LARGE AVALANCHES CLOSE TO BANSKO SKI RESORT IN PIRIN MOUNTAINS – TREE-RING AND NUMERICAL SIMULATIONS ANALYSIS
-
-
Title: THE DESTRUCTIVE POTENTIAL OF LARGE AVALANCHES CLOSE TO BANSKO SKI RESORT IN PIRIN MOUNTAINS – TREE-RING AND NUMERICAL SIMULATIONS ANALYSIS
Proceedings: International Snow Science Workshop Proceedings 2023, Bend, Oregon
Authors:
- Momchil Panayotov [ University of Forestry, Sofia, Bulgaria ] [ Bulgarian Extreme and FreeSkiing Association (BEFSA), Sofia, Bulgaria ]
- Nickolay Tsvetanov [ University of Forestry, Sofia, Bulgaria ]
- Marc Christen [ WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland ]
- Peter Bebi [ WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland ]
- Perry Bartelt [ WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland ]
Date: 2023-10-08
Abstract: In our study we reconstruct past avalanches in three couloirs in close proximity to Bansko ski resort in Pirin Mountains, Bulgaria. We combined tree-ring analysis, satellite images and historical aerophotos to evaluate the effects of large avalanches. With the use of the avalanche-simulation software RAMMS (extended) we calculated the parameters of large avalanches, modelled the extent of forest destruction and compared the outputs with the reconstructed outlines of avalanches which occurred in the studied couloirs in the 20th century. We therefore linked avalanche return period to snow conditions and avalanche friction parameters. The analysis of the 455 tree-ring cores showed that large avalanches occurred in the studied area almost every decade. The RAMMS simulations revealed that avalanches with large release areas, release depths of 100 cm or more and parameters typical for 100-year return period dry snow avalanches could cause the extent of damages reconstructed by the tree-ring analysis. Observations and video records in the last decade show that recent avalanches correspond to parameters of 10-year return period avalanches with few exceptions as the avalanche in Palashica couloir on 25.01.2021 and "Second couloir" on Todorka NW face on 24.01.2019. Some of the 30-year return period avalanches could also produce more severe damages. Our simulations demonstrate that larger avalanches similar to those that have occurred in Palashica couloir at the end of the 19th and during the 20th century could seriously affect the base area of Bansko ski resort. It is therefore necessary to address this risk with high priority.
Object ID: ISSW2023_O13.05.pdf
Language of Article: English
Presenter(s): Momchil Panayotov
Keywords: avalanches, avalanche-forest interaction, Pirin, tree-ring analysis, RAMMS
Page Number(s): 1176 - 1182
-