Holocene abrupt climate fluctuations: Sedimentary record from the inner-shelf mud area of the East China Sea

Abstract

Sediment core MZ02 from the inner-shelf mud area of the East China Sea was studied to address paleoclimate and marine environment change during the Holocene epoch. This core was analyzed for accelerator mass spectrometry (AMS) 14C dating, grain size, magnetic susceptibility, geochemical index (Al/Ti, Ba/Ti), oxygen isotope, and Mg/Ca ratio of benthic for a minifera. Three significant climate change events were identified, which occurred at 8.4, 7.2 and 6.2 ka BP, respectively. The sediments are characteristic of the period, with coarse grain size and smaller Mg/Ca and δ 18O values. The study revealed that the characteristics of abrupt climate fluctuation were consistent with monsoon and paleoceanographic records of the adjacent land and tropical Pacific. There are century solar cycles in the sedimentary record. The 200-year cycle is the most significant, suggesting that solar activity was the major cause of rapid climate change in the research area during the Holocene.