Chronology of the short-term climate changes during the Holocene in northwestern Russia and its correlation with the solar activity variations

A more accurate radiocarbon dating of short-period climate changes in the Holocene requires to take into account short-term changes in variation of the 14 C concentration in the atmosphere, which could lead to a dating error of up to 300 years. To eliminate this potential problem, Bronk Ramsey’s model was used, based on a comparison of the radiocarbon dates with the calibration curve. Using this model, a corrected (i.e., modeled) age was established for the entire series of previously determined radiocarbon dates obtained from the Nikolsko-Lyutinskoye, Shirinsky Mokh, and Sambalskoye raised bog sections in northwestern European Russia. The deviations of the average annual temperature from its modern value (∆T), presented in previous publications as graphs, were converted into digital form. Using this model, a refined calendar chronology was established. The chronology of short-period climate changes in the Holocene demonstrates the synchronicity of short-term climate fluctuations. In most cases, it agrees well with the chronology obtained in the study of natural objects (lakes, bogs, marine sediments, and polar glaciers), as well as with the advances of mountain glaciers. The chronology of short-period climate changes is compared to the changes in solar activity, established by using concentrations of cosmogenic isotopes: 14 C in tree rings, and 10 Be in polar glaciers. The synchronicity of short-term climate fluctuations and variations of solar activity in the Holocene has been established, and it suggests that changes of solar activity are one of the main causes of short-period climate fluctuations in the Holocene.