东北及邻近地区累积积雪深度的时空变化规律

利用东北及邻近地区1960-2006年123个地面测站逐日积雪观测资料和同时期气象要素资料,采用面积权重、EOF、小波分析和功率谱方法分析了东北全年及各季节累积积雪深度的时空变化特征,结果表明:近50年来东北及邻近地区累积积雪呈缓慢增加趋势,具体到各个季节上,秋季积雪趋势基本稳定,冬季积雪显著增加,春季积雪显著减少,年...

Temporal-Spatial Characteristics of Cumulative Snow Depth in Northeast China and Its Vicinity

Based on the snow cover data and meteorological element data at 123 meteorological stations in Northeast China during the period of 1960-2006, the spatial and temporal characteristics of snow cover are analyzed by the area weighted method, empirical orthogonal function, Morlet wavelet analysis and power spectral method. The results show that the cumulative snow depth in Northeast China is increasing slowly in the recent 40 years. The cumulative snow depth is no obvious changes in autumn, increasing in winter, and decreasing in spring, in which the increasing cumulative snow depth in winter is the key factor to the increasing annual cumulative snow depth. We hold the opinion that there are three main spatial patterns of cumulative snow depth in Northeast China by using EOF method, of which, the first pattern is consistently more (less) than normal, the second pattern is a seesaw between southern (northern) region and northern (southern) region, and the third pattern is a seesaw between central region (other region) and other region (central region).There is a quasi period of 7 years revealed by Morlet wavelet analysis and power spectral method, its period displays a decreasing trend and has a good response to the global warming.