Abstract. The experience of calibrating Eglit's avalanche model using data about the avalanche travel distance lengths and velocity data from the Zailiyskiy Alatau range (Kazakhstan) is discussed. Empirical equations are proposed that describe the dependence of the friction coefficients on the avalanche volume and type.

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The assessment and forecast of avalanche danger are very important means of preventing avalanche fatalities, especially in recreational areas. The use of artificial intelligence methods for these purposes significantly increases the accuracy of avalanche forecasts. The purpose of this re-search was to improve the methods for assessing and forecasting avalanche danger in the Ile Alatau Ridge. To create a training sample, the data from three meteorological and two avalanche stations for the period from 2002 to 2022 were used. The following predictors were chosen: air temperature, snow cover depth, precipitation, and snowpack stability index. The subject of the assessment and forecasts was the level of avalanche danger, assessed on a five-point scale. The program Statistica StatSoft was used as a neurosimulator. When forecasting avalanche danger, the predictive values of air temperature and precipitation, obtained from numerical weather forecast models, were used. The model correctly assessed the current level of avalanche danger in 90% of cases. The forecast of avalanche danger was justified in 80% of cases. The artificial intelligence program helped the avalanche forecaster to improve the forecast quality. This method is currently being used for compiling an avalanche bulletin for two river basins in the Ile Alatau.

Abstract:The presentation describes the methods and shows the results of GLOFs' danger estimation in Ile and Zhetysu Alatau ranges (Kazakhstan). The catalogues of glacial lakes were made following the results of satellite images processing. The catalogue contains the data of 186 glacial lakes in Ile Alatau and 577 lakes in Zhetysu Alatau. According to the bathymetric data of 35 glacial lakes the dependences of volume on lake's area for proglacial and moraine lakes were developed and lake's volumes were calculated. There are 32 lakes in Ile Alatau and 110 lakes in Zhetysu Alatau with water volume more than 100,000 m 3 . The most hazardous lakes have the following characteristics: 1) the lake volume exceeds 100,000 m 3 , (2) the lake is proglacial, (3) the dam is a young moraine with an ice core, (4) there are sites with the steep of more than 15 о spreading for more than 500 m down the valley, and (5) there are important non-protected objects in the mudflows affected area. There are 14 the most hazardous glacial lakes with very high level of GLOF danger: 6 lakes in Ile Alatau and 8 lakes in Zhetysu Alatau.

Snowiness and avalanche activity are very important natural characteristics of mountain areas. They have a great influence on the possibility of areas’ development, especially regarding winter recreation. This article considers the interannual variability of snowiness and avalanche activity in the Ile Alatau Ridge (Northern Tien Shan), which belongs to the areas with a continental snow climate. The sum of winter precipitation and snow depth are used as snowiness indices, and the indices of avalanche activity are the total avalanche volume, maximum avalanche volume and number of avalanches. The work uses archival data for the period from 1966 to 2022. Interannual variability of snowiness and avalanche activity indices and long-term temporal trends were assessed, correlation between these indices was studied, and extreme values with different return periods were calculated. The relationship between years with a high snowiness and years with a high avalanche activity, as well as years with a high avalanche activity and years with a large number of avalanche victims and high avalanche damage has been studied. Similar studies have not been previously carried out for the areas with a continental snow climate. Snowiness indices have weak, non-significant, increasing temporal trends. The total avalanche volume has a non-significant decreasing temporal trend, and the maximum avalanche volume has a significant decreasing one. The number of avalanches has a significant increasing temporal trend. This study could be relevant for understanding the features of temporal variability of snowiness and avalanche activity in the mountainous regions with a continental snow climate.