基于气象要素的中国积雪类型划分及积雪特征分布

Snow cover classification based on climate variables and its distribution characteristics in China

积雪分类对于深刻认识积雪性质及其时空分布具有重要意义。积雪是气候的产物,气象参数是导致积雪性质差异的主要因素,利用实测的气象参数能够对积雪性质进行大范围的有效分类。应用长时间序列高时空分辨率全国地面气象驱动格网数据集,提取中国区域冬季大气温度、降水量和近地表风速信息,基于冬季气象要素的二叉树积雪类型划分方法,采用Sturm等提出的季节性积雪类型划分体系,对中国区域的积雪类型进行了划分,相比Sturm等的积雪分类结果空间分辨率显著提高,利用"中国积雪特性及分布调查"项目2017-2018年全国实测雪坑数据,描述了积雪类型对应的空间统计分布特征,为制定符合中国区域特色的积雪类型分类系统奠定了基础。积雪分类结果表明:中国区域的积雪类型划分为5种,分别是大草原型、泰加林型、苔原型、高山型及瞬时型,不同的中国积雪类型表现出与Sturm等的分类描述有所不同的积雪特性。

Snow cover classification is of importance for knowing snow properties and their temporal and spatial distribution.It is the climate that ultimately determines the physical characters of snow cover through temperature,precipitation and wind.Therefore,snow cover classification can be derived from the important climate variables.In this paper,a snow cover classification in China is put forwards based on binary system of the three climate variables proposed by Sturm et al.using long serise of China meteorological dataset,and the snow cover characteristics’distribution is statistically analyzed and validated by in-sit measured data from Science&Technology Basic Resources Investigation Program of China(investigation on snow characteristics and their distribution in China),which laid the foundation for formulating a snow cover classification system with China’s regional characteristics.The results show that spatial resolution of the snow cover classification in this paper has increased significantly as compared with that in the study of Sturm et al.The snow cover types in China can be divided into five types:prairie,taiga,tundra,mountain and ephemeral types.Different types of snow cover in China show snow characteristics different from Sturm-Holmgren-Liston(SHL)classification.