利用长时间再分析资料和台站观测资料以及反映太阳周期活动的太阳黑子数资料，研究了太阳活动11年周期对东亚冬季风与随后夏季风关系的影响和过程。结果表明，弱（强）的东亚冬季风后的次年春、夏季在西北太平洋上空往往出现反气旋（气旋）式环流异常。通过将东亚冬季风指数分解为与 ENSO 有关的部分以及与ENSO无关的部分，进一步证实东亚冬、夏季风之间的联系主要来自于与ENSO有关的东亚冬季风异常。在此基础上着重分析了太阳活动对东亚冬、夏季风关系的影响和过程。研究表明，太阳活动显著影响了东亚冬季风与ENSO的关系，在太阳活动偏低年ENSO与东亚冬季风的关系更为密切。并且，对应与ENSO有关的东亚冬季风异常，当太阳活动偏低（LS）时西北太平洋附近的异常反气旋明显增强，范围扩大，其西北侧的西南气流强度偏强并向北延伸，从而使春季多雨地区绵延到内蒙古乃至西北地区；而夏季降水主要集中在长江流域中游，表明是一个强的夏季风年。然而，在太阳活动偏高（HS）年的次年春、夏季，不论是环流异常还是降水场的异常都明显偏弱。这说明东亚冬季风与随后夏季风的关系在 LS 年要比 HS 年更紧密。对海温异常的分析则进一步表明，LS （HS）年从冬季至夏季与ENSO有关的东亚冬季风异常相联系的印度洋及热带西太平洋海温正相关范围明显偏大（小）；而赤道东太平洋的显著正海温异常衰减迅速（缓慢）。上述海温异常的差异是西北太平洋反气旋能否从冬季持续到夏季的重要原因，并可以很好地解释太阳活动对东亚冬、夏季风关系的影响。%anomalous anticyclone (cyclone) over the western North Pacific (WNP), which can persist from winter into the following summer. By dividing the EAWM index (EAWMI) into an ENSO-related part (EAWMI-EN) and an ENSO-unrelated part (EAWMI-res), the authors demonstrate that such an EAWM-EASM link comes mainly from the EAWMI-EN part. Further examinations indicate that the EAWM-ENSO relationship depends on the solar cycle with more robust relationship in the low solar activity (LS) categories. Moreover, during positive EAWMI-EN phases, the WNP anticyclonic anomalies are enhanced when solar activity is low and the enhanced southwesterly to its northwest flank extends more northward. Hence, the regions with above-normal rainfall stretch to the Inner Mongolia and Northwest China in the spring, and a notable wet center is located in the middle reaches of the Yangtze River in the summer, which indicates a strong EASM years. However, in the high solar activity (HS) years, both the circulation and the rainfall anomalies are much weaker. There tends to be a much stronger EASM after a weak EAWM-EN during the LS phases than during the HS phases. The analysis of the sea surface temperature (SST) anomalies demonstrates that in LS (HS) years the ranges of positive correlation covering the Indian Ocean and the western tropical Pacific are larger (smaller) while the decaying of the SST anomalies in the eastern equatorial Pacific is rapid (slow) from the winter to the following summer. These SST anomalies contribute to differences in the persistence of the WNP anticyclone, and thus explain why a closer EAWM-EASM relationship is established during LS years than HS years.
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