Умови сходження лавин у масиві Чорногора (Українські Карпати)

Abstract

There are about eighty avalanche geocomplexes, which belong to different classes according to avalanche activity, in the mountain massif Chornohora. One of the main tasks is an investigation of natural conditions of avalanche formation because of snow mass slide process influence on the environment and human activities. Snow-avalanche formation conditions within landscape complexes of Chornohora mountain massif in Ukrainian Carpathians, depending on group of factors (landscape structure, meteorological quantity and phenomenon and other), are considered. Special attention is paid to study the morphological structure of snow and stratification structure of snow cover as the main avalanche slide factors. The landscape structure and relief of territory with avalanche activity are analyzed. All avalanche genetic types, which are identified in the Chornohora mountain massif, are located on the steep and very steep slope on old-glacial relief forms (slope steepness – 15–45° (Miller, 1966)). Avalanche activity within research territory limits of the Pozhyzhevska snow-avalanche station was analyzed and short characteristic of avalanche subperiod during research time was presented. The dynamics of snow depth and snow cower structure, temperature regime of air and snow during research period was investigated. The main indexes of meteorological phenomena, which are typical for the days when avalanche activity was identified, were determined. Analysis of meteorological quantity and phenomenon indexes is realized on the base of own research information and technical report of Pozhyzhevska snow-avalanche station. Based on the results of the investigation natural conditions of snow avalanche slide of all genetic types (polygenetic (inducted by snowfall and blizzard) and epigenetic (inducted by the melt of snow – insolation and advection process)) were determined. The typical profile of snow cover, which is characterized by avalanche sliding process, is proposed for every genetic type of avalanche. The characteristics of snow profiles are presented in figures. Key words: avalanche, Ukrainian Carpathians, snow cover, meteorological phenomena.