TRENDS OF CLIMATIC CHANGES IN DENSITY OF YEAR RINGS

Abstract

The relevance of the research is caused by the need to conserve forest zones and development forest industry. The main aim of the research is to use long-term trends in characteristics under study such as density of annual rings, changes in total ozone in the atmosphere and the de Martonne aridity index for assessing climate change. In addition, another aim of the study is to decompose the dendrochronological signal into components associated with individual factors. Objects of the research are time series of the total ozone content in the atmosphere, density of annual rings and the de Martonne aridity index. Methods: time series analysis, spectral singular analysis (Caterpillar-SSA method), F-criterion. Results. The authors have analyzed the dendrochronological and climatic data in two numerical experiments (Data Mining). This allowed obtaining the information for the forecast of annual growth of coniferous trees and linking the individual components of the dendrochronological signal with the influence of certain factors (temperature, precipitation, ultraviolet-B radiation, etc.). The use of the Caterpillar-SSA method in combination with previously made factor analysis of the dispersion of the dendrochronological series helps allocate climatic and sensitive to ultraviolet-B radiation components in separate time series. The obtained components can be used for long-term prediction of wood density. Ultraviolet-B radiation (total ozone content) and climate signal can be used for reconstruction and prediction of atmospheric characteristics (total ozone content, the de Martonne aridity index). Equations of nonlinear trends of maximum density of annual rings of coniferous trees, of total ozone content, of the de Martonne aridity index also allow obtaining a reliable prediction of the conditions of formation of annual rings and wood density, but for a shorter period, as they do not consider the cyclicity of climatic processes.

Keywords

• time series
• trend
• prediction
• dendrochronological method
• singular spectral analysis