Dataset Information

Evidence for solar cycles in a late Holocene speleothem record from Dongge Cave, China.

ABSTRACT: 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 ?(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 ?(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).

SUBMITTER: Duan F

PROVIDER: S-EPMC4044623 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Evidence for solar cycles in a late Holocene speleothem record from Dongge Cave, China.

Duan Fucai F Wang Yongjin Y Shen Chuan-Chou CC Wang Yi Y Cheng Hai H Wu Chung-Che CC Hu Hsun-Ming HM Kong Xinggong X Liu Dianbing D Zhao Kan K

Scientific reports 20140604

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 ...[more]

PMID: 24894978

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Dataset Information

Evidence for solar cycles in a late Holocene speleothem record from Dongge Cave, China.

Publications

Evidence for solar cycles in a late Holocene speleothem record from Dongge Cave, China.

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