东北冷涡环流及其动力学特征
Northeastern China Cold Vortex Circulation and Its Dynamical Features
中文摘要：
主要总结了东北冷涡形成和维持的动力学原因：（1）大兴安岭/小兴安岭的地形以及临海的水汽条件有利于东北地区移动性冷涡系统的形成和发展。（2）与欧亚大陆阻塞型环流相联系的准纬向低频Rossby波活动将其波能量直接频散到东北地区，形成冷涡环流。（3）源自东北亚阻塞型环流以及副热带异常环流的Rossby波均可经向传播到东北地区，有利于东北冷涡环流的维持（尤其在仲夏和晚夏）。（4）与相邻阻塞型环流有关的对流层中低层冷空气活动可强迫出东北地区局地上传Rossby波，致使冷涡环流形成和维持。（5）来自东北地区上游的瞬变天气扰动与下游异常环流型相互匹配，形成有效的瞬变涡动强迫作用，使冷涡环流持续维持。（6）负位相西太平洋（WP）遥相关型是东北冷涡活动的下游背景环流型，其盛行是东北冷涡环流反复出现和持续维持的一个重要原因。
中文关键词：
东北冷涡，阻塞型环流，Rossby波，瞬变涡动强迫，WP遥相关型
KeyWords：
northeastern China cold vortex, blocking-type circulation, Rossby wave, transient eddy feedback forcing, western Pacific pattern
Abstract：
The dynamical mechanisms associated with the formation and maintenance of Northeastern China Cold Vortex (NCCV) are summarized in this paper: (1) The topography conditions related to the Greater and Lesser Hinggan Ling ranges and the water vapor condition facilitated by the neighboring seas are favorable to the formation and development of the migrating cold vortex system over the Northeastern China; (2) The NCCV circulation may be directly formed due to the downstream energy dispersion of the quasi-zonal low-frequency Rossby waves that are emanated by the upstream blocking-type anomalous circulation over the Eurasian continent; (3) The meridional propagations of Rossby waves from the blocking-type circulation over Northeastern Asia and from the subtropical anomalous circulation are favorable to the maintenance of the NCCV circulation, in particular, in mid- and late summer; (4) the formation and maintenance of NCCV circulation can also be caused by the upward propagation of Rossby waves over Northeastern China, which is forced by the cold air activity in the lower and mid-troposphere associated with the neighboring blocking-type circulation; (5) The effective transient eddy feedback forcing, due to the interaction between the transient synoptic disturbances from upstream regions and the downstream basic flow pattern, leads to the persistent maintenance of the NCCV circulation; (6) The western Pacific (WP) pattern is the background downstream basic circulation pattern of the NCCV circulation and its dominance is the primary cause of the recurrence and persistence of the NCCV activity.