雪崩危险度评价的类型、特征和方法

在提出“积雪单元”概念的基础上,将雪崩危险度评价分为区域雪崩危险度评价和点位雪崩危险度评价。从发生学角度,论证、筛选出发生危险度评价的4个主导因素,即气候、积雪厚度、坡度和植被类型与覆盖度,并提出了明确的指标体系。详细论证了两类评价各自的特征、操作性评价程序和方法。区域雪崩危险度评价是在划分积雪单元的基础上,评定各单元的等级高低并进行制图;点位雪崩危险度评价则涉及到雪崩发生点位和可能的承灾点位,分为发生危险度评价和到达危险度评价,可根据已有的统计资料来预测其概率。

Categories and methods of avalanche hazard evaluation

The "snowpack unit" is initially defined. Upon the new concept, the avalanche hazard evaluation is distinguished into regional evaluation and site evaluation. Evaluating factors are screened, and four ones among them are shown to be the main factors. They are climate, snowpack thickness, slope, and vegetation types and coverage. Their grading criteria for release hazard evaluation are also determined. The characteristics, operational procedure and methods, for each kind of the evaluation, are explored in detail. The regional evaluation of avalanche hazard, based on dividing snowpack units, is to determine the grades of the units and mapping. The site evaluation of avalanche hazard, which is related to the release site and the possible disaster-suffering site, can be divided into release hazard evaluation and reaching hazard evaluation. The probability for each of the both, as well as a combined probability can be obtained by using statistical data.