基于GIS的东北及邻近地区积雪深度空间化方法

GIS-based Spatializing Method for Estimating Snow Cover Depth in Northeast China and Its Nabes

根据近50 a东北及邻近地区122个地面测站逐日积雪深度观测资料,采用REOF方法划分为5个气候区,利用DEM资料建立经度、纬度、海拔高度3个宏观地形因子以及坡度、坡向和开放度3个微观地形因子的数据库,并结合三维二次趋势面方法对研究区域雪深进行GIS模拟。结果表明:宏观地形因子与雪深呈较好的正相关关系,大、小兴安岭是东北地区积雪分布较多区域,大致按山脉走向分布,海拔高、纬度高的地区雪深较大。分区模拟,微观地形因子对积雪深度的影响增大,突出积雪深度分布的局地特征,同时相对误差显著减小。

In this study,five climate zones were delimited using the rotated empirical orthogonal function（REOF） method base on the data of snow cover depth and other meteorological factors,observed by 122 meteorological stations in northeast China in recent 50 years.A database of three terrain factors（longitude,latitude and altitude） and three micro-terrain factors（slope,exposure and openness） was derived using digital elevation model（DEM） and GIS to simulate snow cover depth in northeast China with the mathematical theorem of trend simulation and stepwise regression.The results showed that there was a positive correlation between the macro-terrain factors and the snow cover depth.Snow cover depth was thick in the Da Xing＇an Mountains and Xiao Xing＇an Mountains in northeast China,and it was increased with the increase of altitude and latitude.Delimitation of the climate zones reveals that the micro-terrain factors could increase their effects on snow cover depth,gives prominence to local features of snow cover depth distribution,and reduce the relative errors.