东北地区夏季旱涝的区域特征及水汽异常输送

Regional features of summer drought and flood in Northeast China and corresponding abnormal water-vapor transportation

应用东北地区91个站46 a的夏季逐日降水资料和相应的NCEP/NCAR逐日水汽输送资料,通过旋转正交经验分解法分析了该区夏季旱涝的区域特征,并进一步研究了各分区旱涝年的水汽异常输送特征。结果表明,东北地区的夏季降水异常具有明显的区域特征,大致可分为6个独立的区域。分别分析了各区域旱涝年与降水正常年水汽输送的差异,发现各区域旱涝年的异常水汽输送路径和关键区均存在明显的不同,且旱涝年异常水汽输送并不是简单的反位相。

By using the data from 91 stations in Northeast China about daily summer rainfall from 1955 through 2000 and corresponding NCEP/NCAR daily water-vapor transportations data, the regional characteristics of summer drought and flood in Northeast China is analyzed by employing REOF, and further research on features of abnormal water-vapor transportation is carried out. The results show that the abnormal summer rainfall in Northeast China has obvious regional characters, and the region may be divided into six independent areas approximately. By investigating the differences of water-vapor transportation between abnormal drought/flood years and normal years, it is found that the abnormal water-vapor transportation paths and key part in drought/flood years have marked differences among the areas, and that the abnormal water-vapor transportation in drought years is not simply contrary to that of flood years.