青藏高原冬春积雪特征及其对我国夏季降水的影响  

Characteristics of Tibetan Plateau Snow Cover in Winter and Spring and Their Influences on Summer Rainfall over China

作　　者：张薇 宋燕[2] 王式功[3,4] 李智才 Zhang Wei;Song Yan;Wang Shigong;Li Zhicai(Fangshan District Meteorological Service,Beijing 102488;Training Centre,China Meteorological Administration,Beijing 100081;Chengdu University of Information Technology,Chengdu 610225;Zunyi Academician Work Center,Guizhou,Zunyi 563000;Shanxi Climate Center,Taiyuan 030006)

机构地区：[1]北京市房山区气象局,北京102488 [2]中国气象局气象干部培训学院,北京100081 [3]成都信息工程大学大气科学学院,成都610225 [4]贵州省遵义院士工作中心,遵义563000 [5]山西省气候中心,太原030006

出　　处：《气象科技》2019年第6期941-951,共11页Meteorological Science and Technology

基　　金：国家自然科学基金项目（41575091）;中国气象局气象干部培训学院2018年科研项目“中国区域气候影响因子研究”资助

摘　　要：本文利用国家气象中心提供的逐日地面积雪深度和积雪日数数据,以及NOAA的大气环流再分析资料,通过合成分析等方法,对1961-2013年青藏高原冬春季积雪高原整体、高原东部、高原西部进行了年际和年代际趋势分析,结果表明,青藏高原整体冬、春季积雪的变化趋势一致,雪深呈现“少雪-多雪-少雪-多雪”的变化趋势,积雪日数呈现“少雪-多雪-少雪”的变化趋势。高原东(西)部积雪在20世纪60-70年代均明显增加,20世纪80-90年代均减少,20世纪90年代末东部春季和冬季积雪减少更为显著,而西部地区除了春季积雪日数变化不大,春、冬季积雪雪深和冬季积雪日数均明显增加。其次,对青藏高原东、西部地区多(少)雪年的划分,发现高原东部和西部地区积雪异常年对应的大气环流形势也存在差异。最后,进一步分析了青藏高原不同区域积雪异常年环流形势变化特征及其对我国夏季降水的影响,发现高原东(西)部积雪异常年时我国夏季降水分布存在显著差异,因此,在将高原积雪作为气候预测因子的时候,应当考虑东部和西部积雪异常不同所产生影响的差异。In this paper,based on the data of daily snow depth(SD)and the number of days with snow cover(NDSC)from the National Meteorological Information Center and the atmospheric circulation data from NOAA reanalysis,by using the Empirical Orthogonal Function(EOF)decomposition,composite analysis,and other statistical methods,we examine the interannual and interdecadal variations of winter and spring snows in terms of the number of days with snow cover(NDSC)and snow depth(SD)in the entire Tibetan Plateau,the eastern Tibetan Plateau(ETP),and the western Tibetan Plateau(WTP),respectively,and found that in the past 53 years(1961 to 2013),the temporal trends of winter and spring snows averaged over the entire Tibetan Plateau are general sim ilar.The interdecadal variations of SD exhibit the feature of“less-rich-less-rich”than norm al,and those of NDSC shows the feature of“less-richless”than norm al.For the temporal trends of snow cover in two regions(ETP and WTP),snows increased significantly in the the 1960s and 1970s and reduced in the 1980s and 1990s for both regions.However,the trends were obviously different since the late 1990s,when the snow cover reduced significantly in the ETP whereas it significantly increased in the WTP except for the spring NDSC that showed no apparent trends.Then we identify the typical years with anomalous snow cover in the ETP and WTP,respectively,and investigate the features of snow cover anomalies and the associated atmospheric circulation anomalies.Finally we investigate the impacts of snow cover anomalies in the Tibetan Plateau on the summer rainfall over China.The results show that significant difference exists in the temporal variations of snow cover for the different regions of the Tibetan Plateau.The results also show apparent correlation between snow cover variations in the Tibetan Plateau and summer rainfall in China.Therefore,it is necessary to take into account the different impacts exerted on summer rainfall by snow cover anomalies in different regions of the Tibetan Platea

关 键 词：青藏高原积雪 冬春季积雪异常 中国夏季降水 合成分析 

分 类 号：P468.025[天文地球—大气科学及气象学]