The leading pattern of boreal spring 250-hPa meridional wind anomalies over the North Atlantic and mid-high latitude Eurasia displays an obvious wave train. The present study documents the structure, energy source, relation to the North Atlantic sea surface temperature (SST), and impacts on Eurasian climate of this wave train during 1948–2018. This atmospheric wave train has a barotropic vertical structure with five major centers of action lying over subtropics and mid-latitudes of the North Atlantic, northern Europe, central Eurasia, and East Asia, respectively. This spring wave train can efficiently extract available potential energy from the basic mean flow. The baroclinic energy conversion process and positive interaction between synoptic-scale eddies and the mean flow both play important roles in generating and maintaining this wave train. The North Atlantic horseshoe-like (NAH) SST anomaly contributes to the persistence of the wave train via a positive air–sea interaction. Specifically, the NAH SST anomaly induces a Rossby wave-type atmospheric response, which in turn maintains the NAH SST anomaly pattern via modulating surface heat fluxes. This spring atmospheric wave train has significant impacts on Eurasian surface air temperature (SAT) and rainfall. During the positive phase of the wave train, pronounced SAT warming appears over central Eurasia and cooling occurs over west Europe and eastern Eurasia. In addition, above-normal rainfall appears over most parts of Europe and around the Lake Baikal, accompanied by below-normal rainfall to east of the Caspian Sea and over central Asia.

北大西洋和中高纬度欧亚大陆上的北半球春季250hPa经向风异常的主导模式显示出明显的波列。本研究记录了该波列在1948–2018年间的结构，能源，与北大西洋海表温度（SST）的关系及其对欧亚气候的影响。该大气波列具有正压垂直结构，在北大西洋，北欧，欧亚中部和东亚的亚热带和中纬度分别具有五个主要的活动中心。该弹簧波列可以从基本平均流中有效地提取可用势能。斜压能量转换过程以及天气尺度涡旋和平均流之间的正向相互作用都在产生和维持该波列中起重要作用。北大西洋马蹄形（NAH）SST异常通过积极的海-海相互作用而导致了波列的持续存在。具体来说，NAH SST异常会引起Rossby波型大气响应，进而通过调制表面热通量来维持NAH SST异常模式。这个春季的大气波列对欧亚地表气温（SAT）和降雨有重大影响。在波列正向阶段，欧亚大陆中部出现明显的SAT升温，西欧和欧亚大陆东部出现降温。此外，欧洲大部分地区和贝加尔湖周围出现高于正常水平的降雨，而里海以东和中亚地区则出现低于正常水平的降雨。