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A 700-year record (1.0-1.5 a resolution) of the East Asian winter monsoon (EAWM),based on grain-size analysis and AMS14C dating of Core EC2005 from the inner-shelf mud wedge of the East China Sea (ECS),was compared with the Dongge stalagmite δ18O record during the mid-Holocene.The upper muddy section of Core EC2005 has been formed mainly by suspended sediments derived from the Changjiang (Yangtze) River mouth since 7.3 ka BP.High precipitation and a strengthened EAWM might have played key roles in the high sedimentation rate (1 324-1 986 cm/ka) between 5.9-5.2 ka BP.The EAWM strengthened when the Asian summer monsoon weakened,especially around 5500 a BP,which corresponded to a worldwide cold event.The EAWM during the mid-Holocene shows statistically significant solar periodicities at 62 and 11 a.The 5500 a BP cold event might be resulted from orbital forcing and changes in solar activity.
A 700-year record (1.0-1.5 a resolution) of the East Asian winter monsoon (EAWM), based on grain-size analysis and AMS14C dating of Core EC2005 from the inner-shelf mud wedge of the East China Sea (ECS), was compared with the Dongge stalagmite δ18O record during the mid-Holocene. The upper muddy section of Core EC2005 has been formed mainly by suspended sediments derived from the Changjiang (Yangtze) River mouth since 7.3 ka BP. High precipitation and a strengthened EAWM might have played key roles in the high sedimentation rate (1 324-1 986 cm / ka) between 5.9-5.2 ka BP. The EAWM strengthened when the Asian summer monsoon weakened, especially around 5500 a BP, which corresponded to a worldwide cold event. EAWM during the mid-Holocene shows significant solar periodicities at 62 and 11 a. 5500 a BP cold event might be resulted from orbital forcing and changes in solar activity.