Duan Fucai, Wang Yongjin, Shen Chuan-Chou, Wang Yi, Cheng Hai, Wu Chung-Che, Hu Hsun-Ming, Kong Xinggong, Liu Dianbing, Zhao Kan
College of Geography Science, Nanjing Normal University, Nanjing 210023, China.
1] College of Geography Science, Nanjing Normal University, Nanjing 210023, China [2].
Sci Rep. 2014 Jun 4;4:5159. doi: 10.1038/srep05159.
The association between solar activity and Asian monsoon (AM) remains unclear. Here we evaluate the possible connection between them based on a precisely-dated, high-resolution speleothem oxygen isotope record from Dongge Cave, southwest China during the past 4.2 thousand years (ka). Without being adjusted chronologically to the solar signal, our record shows a distinct peak-to-peak correlation with cosmogenic nuclide (14)C, total solar irradiance (TSI), and sunspot number (SN) at multi-decadal to centennial timescales. Further cross-wavelet analyses between our calcite δ(18)O and atmospheric (14)C show statistically strong coherence at three typical periodicities of ~80, 200 and 340 years, suggesting important roles of solar activities in modulating AM changes at those timescales. Our result has further indicated a better correlation between our calcite δ(18)O record and atmospheric (14)C than between our record and TSI. This better correlation may imply that the Sun-monsoon connection is dominated most likely by cosmic rays and oceanic circulation (both associated to atmospheric (14)C), instead of the direct solar heating (TSI).
太阳活动与亚洲季风（AM）之间的关联仍不明确。在此，我们基于中国西南部董哥洞过去4200年（ka）精确测年的高分辨率洞穴石笋氧同位素记录，评估它们之间可能存在的联系。在未对时间序列进行太阳信号调整的情况下，我们的记录在数十年至百年时间尺度上，与宇宙成因核素（14）C、总太阳辐照度（TSI）和太阳黑子数（SN）呈现出明显的峰峰相关性。我们的方解石δ（18）O与大气（14）C之间进一步的交叉小波分析表明，在约80、200和340年这三个典型周期上存在统计学显著的一致性，这表明太阳活动在这些时间尺度上对亚洲季风变化的调制作用十分重要。我们的结果还进一步表明，我们的方解石δ（18）O记录与大气（14）C之间的相关性，要优于我们的记录与总太阳辐照度（TSI）之间的相关性。这种更好的相关性可能意味着，太阳与季风之间的联系最有可能由宇宙射线和海洋环流（两者均与大气（14）C相关）主导，而非直接的太阳加热（总太阳辐照度（TSI））。
