关键词: 北半球环状模, 东北冷涡, 行星波动, 平流层?对流层相互作用, 中长期天气预报

Abstract: The purpose of the study is to investigate influences of stratospheric circulation anomalies on NCV. Using the NCEP/NCAR (daily and month mean) dataset over 1958?2010, the authors performed statistical and composite analyses on the characteristics and three dimensional structures of NCV for stratospheric northern-hemisphere annular mode anomalies. It shows that NCV has more frequent occurrences and longer duration during negative stratosphere NAM anomalies than that during positive NAM anomalies. Composite results show that NCV is stronger during negative stratospheric NAM anomalies than that during positive NAM anomalies. It is also found that during negative stratospheric NAM anomalies NCV is more closely related to downward, eastward and equatorward propagation of stratospheric anomalies, indicating that negative stratospheric NAM may enhance formation and development of NCV and lead to colder weather in Northeastern China. The results have important implications for medium range forecasting NCV in the winter season.

Key words: northern-hemisphere annular mode, northeast cold vortex, planetary waves, stratosphere-troposphere interaction, medium range forecasting