Reconstruction of the Wolf Numbers Based on Radiocarbon Data from the Early 11th Century until the Middle of the 19th Century with Respect to Climate Changes
The results of the reconstruction of Wolf numbers from the 11th century until the middle of the 19th century A.D. based on radiocarbon data are presented. This time span includes the Oort, Wolf, Spörer, Maunder, and Dalton minima of solar activity, as well as the Medieval Solar Maximum (the 12th century and the first half of the 13th century A.D.) and the Late Medieval Maximum (the second half of the 14th century). It is known that the climate changed appreciably over the studied period: there were changes in the global temperature and in the concentration of carbon dioxide in the Earth’s atmosphere; more precisely, there was the Little Ice Age. This work differs from previous reconstructions of other authors in taking into account the influence of climate changes on the radiocarbon content in examined samples at that time span. During the reconstruction, changes in carbon dioxide content and changes in the regimen of carbon dioxide exchange between the ocean and the atmosphere are considered. It is especially important to consider changes in these parameters for the Little Ice Age, which was accompanied by significant changes in global temperature and the carbon dioxide content in the Earth’s atmosphere.
This work from A.I. Kuleshova and Yu.A. Nagovitsyn was supported in part by the Russian Foundation for Basic Research, grant no. 16-02-00090, and Program of Presidium of RAS no. 28.
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