中文摘要：

研究了春季欧亚大陆地表气温的年际变化及其相联系的环流场特征，发现春季欧亚大陆地表气温年际变化呈现为大陆尺度的南北跷跷板式的空间分布特征，即当中高纬度地表气温为正距平时，副热带地区则为负距平，反之亦然。这种空间分布型代表了欧亚大陆中高纬度地表气温年际变化的主要特征。进一步的研究表明，这种变化与前期冬季北大西洋涛动（NAO）有着显著的正相关，而与同期的NAO无关。同时，欧亚大陆地表气温异常存在着明显的从冬到夏的持续性。与东亚初夏气候变化关系的研究表明，春季欧亚大陆地表气温的变化通过影响鄂霍次克高压的变化进一步影响初夏梅雨的变化。当春季欧亚大陆中高纬度地表气温为正距平时，鄂霍次克高压偏强，初夏梅雨较活跃，反之亦然。

英文摘要：

The motivation of this study is to understand the interannual variability of Eurasian thermal condition prior to the summer monsoon season. By using the observation-based surface air temperature data, interannual variability of Eurasian surface air temperature in springtime and related circulation features are investigated. The main analysis methods in this study include principal component analysis, linear regression and composite analysis. It is found that year-to-year variations of springtime Eurasian surface air temperature exhibit as the north-south seesaw spatial pattern on continental scale： Positive anomalies of surface air temperature at mid-high latitudes of Eurasia are accompanied by the negative anomalies over the subtropics of Eurasia, and vice versa. Such spatial pattern represents the main feature of interannual variability in surface air temperature at mid-high latitudes of Eurasia. Further analysis demonstrates that such variations bear significant positive correlations with the preceding wintertime North Atlantic oscillation （NAO）, while there exists no relationship with the contemporary NAO. Much interesting is that Eurasian surface air temperature has obvious persistence from winter to early summer. Studies of the relationship with the early summer climate in East Asia indicate that variability in springtime Eurasian surface air temperature puts impacts on the early summer Meiyu rainfall through modulating the activities of the Okhotsk high. When the mid-high latitudes of Eurasia are warmer, the Okhotsk high tends to be stronger and the early summer Meiyu tends to be more active, and vice versa.