Natural Climate Variability During the Holocene

• Published in: Radiocarbon
• Main Authors: Dergachev, V A, Raspopov, O M, Damblon, F, Jungner, H, Zaitseva, G I
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2007
• Subjects: glacier; Greenland; Greenland ice cores
• Online Access: http://dx.doi.org/10.1017/s0033822200042715; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033822200042715

High-precision radiocarbon age calibration for different terrestrial samples allows us to establish accurate boundaries for many climatic time series. At the same time, the fluctuations of 14 C content reflect solar variability. A bispectrum analysis of long-term series of the 14 C content deduced from decadal measurements in tree rings demonstrates the existence of amplitude modulation, with a period of main modulation of ∼2400 yr. In 14 C time series for the last 11 kyr, major oscillations are distinguished at 8.5–7.8, 5.4–4.7, 2.6–2.2, and 1.1–0.4 cal kyr BP with ∼2400-yr periodicity. High amplitudes in cosmogenic isotope content with a periodicity of about 2400 yr appear synchronous to cooling events documented in Greenland ice cores, to the timing of worldwide Holocene glacier expansion, and to the periods of lake-level changes. This paper focuses on revealing solar forcing on the Earth's climate and about the nature, significance, and impact of sharp Holocene climate variability on human societies and civilizations.