摘要
用１９７３～１９９４年观测资料，研究了东亚中纬冬季雪盖异常对初夏东半球主要流型随季节变化的影响，同时也分析了多（少）雪年份东半球温带地区３０～５０天低频振荡强度以及夏季中国降水量分布的差异．结果表明，近２０年来冬季东亚中纬雪盖强度呈线性增加趋势且迭加较显著的准２年周期变化，它的变化和初夏５００ｈＰａ低频流型逐候演变之间同时存在线性和非线性相关，并且多雪时欧亚大陆大部分地区３０～５０天振荡强度增强，而东北亚地区减小．
The influences of the snow cover anomaly during the winter in the mid latitude region of East Asia on the variations of the dominant low frequency modes with seasons of the Eastern Hemisphere in early summer are studied based on the data from 1973 to 1994,and the differences of the intensity of 30～50 day low frequency oscillation over extratropical Eastern Hemisphere and the summer rainfall over China in snowy and less snowy years are discussed. The interannual variations of winter snow cover at mid latitude in East Asia appear linear increasing and to have the quasi biennial oscillation superimposed,and the relationships between its variation and the evolutions of the dominant low frequency modes are linear or nonlinear correlation at the same time. The intensities of low frequency oscillation are stronger for the most regions of Eurasian continents,but weaker in northeastern Asia in snowy years.
出处
《应用气象学报》
CSCD
北大核心
1998年第4期410-416,共7页
Journal of Applied Meteorological Science
关键词
东亚中纬
雪盖
500hPa
候平均高度
大气环流
Mid latitude region in East Asia Snow cover Mean pentad 500 hPa height Seasonal evolution Nonlinearity
