ИСТИНА

The evaluation of snow avalanches’ contribution into mountain glacier ice accumulation with a lack of direct observational data on snow avalanches and the amount of avalanche-drifted snow deposited on glaciers implies a highly relevant task delivering the important knowledge of one of the least studied components of the glaciers mass balance and it is affected by changing climate. However, in many cases it is not possible to apply commonly accepted methods for the evaluation of avalanche accumulation on the glaciers due to poor data availability and lack of possibilities to obtain the required field data. We present a new approach for the numerical estimation of snow avalanches contribution into accumulation on glaciers without carrying out detailed terrestrial snow surveys based on DEM and meteorological data analysis using GIS and numerical modeling of snow avalanches. Our approach consists of the following steps: DEM analysis; avalanche release, track and run out zones assessment; meteorological data re-calculation for the avalanche release zones; indication of active avalanche release zones and snow fracture height in them during the analyzed winter period; avalanches volumes assessment; numerical simulations of avalanches in three-dimensional terrain using avalanche dynamics program RAMMS; verification – comparison of modeling results with field observations and remote sensing data; evaluation of the contribution of snow avalanches, coming from outside the glacier limits, into the seasonal accumulation on the glacier.