东北区域水汽收支的变化及其与降水的关系

为了明确东北区域水汽收支变化及其与降水的关系,利用1970～2010年NCEP/NCAR逐月平均分析资料、国家气象信息中心提供同期的气象站逐日降水实况资料,对东北区域夏半年（5～9月）区域水汽收支的年（年代）际变化及其与降水的关系、降水偏多（少）年的水汽输送特征进行研究.研究结果表明：（1） 1970年代水汽异常输送主要来自华北地区;1980年代,水汽异常输送主要来自蒙古东部和日本海;1990年代,水汽异常输送主要来自鄂霍次克海;2000年以后,水汽异常自东北区域向西南方向输送.总体而言,1970～1990年代区域内的水汽增加,2000年以后区域内水汽明显大幅度减少.（2）东北区域水汽总收支与夏季降水相关性较好,相关系数可达0.79,通过99％的信度检验,南、北边界的水汽输送对该区域的夏季降水有显著影响.（3）东北地区降水偏多年,西北太平洋上的水汽明显增强;降水偏少年,西风带和西北太平洋的水汽输送明显减弱.

The Variation Features of Moisture Budgets and Its Relationship with Precipitation over the Northeast Area of China

In order to clarify Northeast China moisture budgets change and its relationship with precipitation, the NCEP/NCAR reanalysis data and the observed data from 1970 to 2010 provided by National Meteorological Informa- tion Center are used to investigate the characteristics of the moisture transport in summer half year （May. -Sept. ）, the annual and decadal variation of region moisture budgets and its relation to precipitation and characteristics of mois- ture transport in the more or less rainfall years. Some new conclusions are drawn： （1） In the 1970s, the mainly anomalous moisture transportation was from North China into Northeast of China; that was from North of Mongolia and Japan Sea in the 1980s; the anomalous moisture transport mainly from Sea of Okhotsk in the 1990s; the anoma- lous moisture transport from northeast to southwest since 2000. On the whole, the decadal variation of moisture bud- gets increase from 1970s to 1990s and abruptly decrease after 2000. （2）The moisture budgets are well related to the precipitation in summer in the Northeast China, the correlation coefficient is 0.79, which is marked positive correla- tion. The moisture transport from southern boundary and northern boundary has significant effect on the summer rainfall over Northeast China. （3） In the more rainfall years of Northeast China, the water vapor over Western Pacif- ic increase remarkable; the moisture transport over westerly belt and Northwestern Pacific abruptly decrease in the less rainfall years.