Variation of H 2 O, CO 2 , and CO 2 Isotope Composition in Tree Rings of Siberian Stone Pine

The experimental measurements of H2O, CO2, and the carbon isotope content of CO2, vacuum-desorbed from tree rings of the Siberian stone pine disc, have been obtained. It is shown that: 1) certain cyclicity exists in annual trends of H2O and CO2; 2) the amplitude of CO2 cycles has markedly risen after 1960; 3) the annual trend of the CO2 concentration in the rings correlates with an increase in atmospheric CO2 concentration; 4) the carbon isotope content varies with the variation of CO2 concentration in a sample.