Vol. 18, issue 07, article # 13

Abstract:

In the paper it is shown that CO₂ sink from the atmosphere due to photosynthesis in vegetation biota exhibit significant correlation with the variations of ozonosphere during the vegetation season because of the sensitivity of chlorophyll to variations of the level of UV-B radiation. We present the reconstruction results on centuries-old variations of the total ozone (TO) indices from dendrochronological data collected in different regions of the Eurasian continent. The analysis of long-period variations of TO indices has shown that the depressions of the stratospheric ozone on large spatial scales in 1930s (of natural origin) and in the last quarter of the twentieth century (with the effect of anthropogenic factor) had no analogs in the preceding history for at least 400 years. The increase of the level of UV-B radiation in these periods depressed photosynthesis in vegetation biota, with ensuing considerable increase of global CO₂ content in the atmosphere. These periods coincide with periods of global warming in the twentieth century