Research On Glacial Lake Stability Related To Snow Avalanche Based On GIS Technology

With the global climate warming, glacial lake outburst increasingly threat to downstream lives and property. Investigating the glacial lakes and studying the glacial lakes stability, then assessing the glacial lakes risk in local zones and establishing corresponding measures to prevent or reduce hazards is already got attention of some governments and international organizations.The first step of glacial lake stability analysis is to seek and analyse the influence factorsof glacial lakes.The influence factors of different glacial lakes in different areas have obvious differences. In this paper, based on GIS methods and snow avalanche models that used widely in the Europe, the author studied the glacial lake stability relevant to snow avalanche using Remote Sensing images and DEM data,and completed some works as follows in detail:(1) In consideration of the run‐out drive of snow avalanche comes from thecomponent gravity, so in this paper, the snow avalanche run‐out properties can be simplifiedinto water movement. And then flow direction and flow accumulation were computed in the study region. Then take certain extentof flow accumulation as snow avalanche run‐out path.(2)α-βmodel is one of the statistical models which is to estimate snow avalanche run‐out distance and is used to aid decision making about safety region for the travellers and local residents In the Europe. This paper use this model to estimate snow avalanche run‐out distance, based on the result, glacial lakes stability caused by snow avalanche can be analysed.(3)After extractingfactors including elevation、plan curvature、roughness and slope, The potential snow avalanche release zonesin the study areawere be calculated based onAv=(Al+Fy)~*Rg~*S. The result indicated that there are98potential snow avalanche zones in all in the study region.(4) The result of α-βmodel in the study region indicated that there are9potential snow avalanches which can spread into glacial lakes. And these avalanches have threat to downstream glacial lakes.The purpose of this paper is to study whether potential snow avalanche have threat to downstream glacial lakes, and this method is a newly way to retain or remove snow avalanche factor in all the assessment parameters in the assessment of glacial lake stability.