大气环流的年代际变化I.观测资料的分析

利用多种资料分析研究了大气环流(包括几个主要大气涛动、一些主要大气环流系统)的时间变化特征.结果清楚地表明大气环流,无论是热带大气还是中高纬度的大气环流,存在着显著的年代际变化特征,主要为10～20年准周期振荡和30多年准周期振荡.北大西洋涛动(NAO)和北太平洋涛动(NPO)的10～20年准周期振荡有近乎同位相特征,而它们的30多年准周期振荡却有近乎反位相变化.西太平洋副高强度与北美大槽强度的变化在10～20年时间尺度既有同位相情况也有反位相情况;但在30多年时间尺度却是基本同位相的.西太平洋副高强度与东亚大槽强度变化在30多年时间尺度也是基本同位相的,且副高变化超前约5～7年.

Interdecadal Variations of Atmospheric CirculationI. Observational Analyses

Through observational analyses of the temporal variations of atmospheric circulation, including the key atmospheric oscillations and the primary atmospheric circulation systems, the results strikingly show that the distinct interdecadal variations exist not only in the tropical atmosphere but also in the mid-high latitude atmospheric circulation. The principal interdecadal oscillations refer to 10-20 years and more than 30 years quasi-Periodical waves. The phase of North Atlantic Oscillation (NAO) covering 10- 20 years time scale well agrees with that of North Pacific Oscillation (NPO), but for more than 30 years oscillation, they are nearly out of phase to each other. In the time scale of 10-20 years, some time the phase of subtropical high strength in the western Pacific region is consistent with that of North American trough strength, some time they are out of phase. But, during the period of more than 30 years their phases are basically parallel. Subtropical high strength in the western Pacific region is mainly in phase to East Asian trough strength in the time scale of more than 30 years, and meanwhile the former leads the later about 5 - 7 years.