在分析东亚地区夏季海平面气压场与中国东部6区域干湿指数关系的基础上,重建了公元960—2000年近千年东亚地区夏季海平面气压场的格点资料,并对重建效果进行了检验。同时,依据重建的海平面气压场资料定义了近千年东亚夏季风强度指数,探讨了近千年东亚夏季风的变化特征。结果表明:(1)重建的近千年东亚地区的海平面气压场具有一定的可信度,它为研究更长时间尺度的东亚夏季风变化特征提供了基础;(2)东亚夏季风指数存在60~70 a、30~40 a、10~20 a的显著周期变化;(3)近千年东亚夏季风的强度指数主要经历过9次明显的趋势突变。其中,13世纪30年代东亚夏季风的强度指数经历了最显著的振动。
Based on the well coupling relationship between the six regional dry/wet series and data of the East Asian Sea Level Pressure(SLP),SLP in summer was reconstructed during 960-2000 A.D.and then the results of the reconstruction were tested.Meanwhile,the East Asian summer monsoon index(EASMI) was defined by using the reconstructed SLP and the evolution of the East Asian summer monsoon(EASM) was discussed during the last millennium.The results show that the reconstructed SLP has certain reliability in the East Asian during the millennium,and it provides foundation for studying the long-term variation of EASM.The periods of 60~70 a,30~40 a and 10~20 a were discovered in EASMI.The nine times abrupt changes were found in EASMI and the most significant vibration occurred in 1230's.