| چکیده انگلیسی مقاله |
Introduction One of the natural disasters that threaten residential areas and roads in mountainous regions is mountain falls, including rockfalls, avalanches, and landslides. Avalanches carry large amounts of snow, rocks, ice, and debris downstream in mountainous areas. The occurrence of avalanches is a significant natural hazard that results in considerable human and financial losses, making the study of factors influencing avalanches and their simulation crucial for managing this phenomenon. Materials and methods In this study, the factors affecting snow avalanches (both terrestrial and meteorological) were examined using the RAMMS simulation model in the Central Alborz Velayat Rood (Dizin Road), Alborz Province. Topographic and geomorphological factors, such as slope, aspect, curvature, topographic position index (TPI), terrain roughness index (TRI), and topographic wetness index (TWI), were analyzed using a digital elevation model (DEM) with a 6×6 cm² pixel size obtained by drone. Meteorological factors, including rainfall, temperature, and wind, were also considered. The RAMMS simulation model was then used to estimate avalanche components such as speed, pressure, and height within the study area. Results and discussion The results indicated that slope and aspect, as topographic indicators, have a significant impact on snow avalanche formation and occurrence. The largest portion of the region, covering 5.7 hectares (54.6% of the study area), with a northeast aspect and slopes of 60 to 120%, was identified as having the highest avalanche potential. Additionally, the RAMMS simulation model results showed that the average and maximum avalanche speeds in the region were 5.3 m/s and 16 m/s, respectively. The average effective avalanche pressure was 7 kPa, with a maximum of 45 kPa. The estimated avalanche height indicated that the average avalanche height in the runout area (residential areas) was 4.5 meters, with a maximum height of 10 meters, categorizing it as a large avalanche. Conclusion Understanding avalanches and their dynamic characteristics is essential for predicting and controlling this hazardous natural phenomenon. Identifying avalanche types (wet, slab, or powder) can greatly assist experts in managing and proposing control methods. In this study, maps, meteorological data, and geomorphological parameters such as curvature, TPI, TRI, and TWI, along with field observations, were used to identify accumulation areas, track zones, and runout zones. The study identified the key factors influencing avalanche occurrence in the region, including high slopes (60-120%), slope orientation (north and northeast), and climatic factors such as precipitation and temperature. The average avalanche height in the runout area (residential areas) was 4.5 meters, with a maximum of 10 meters. This study indicates a high potential for avalanches and associated damage in the area, underscoring the need for management and control programs to mitigate possible harm. |