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It is well known that tree-ring formation mechanism is influenced by the number of climate and non-climate factors. An analysis of simulated and observed cell production of tree rings allows to separate the climate signal from other local effects (e.g., fire or insects), which can be fixed in the tree ring profile. One of principal indicators in tree ring structure is a distribution of radial cell sizes during growing season. In this work the process-based tree-ring VS-model was used to resolve the critical processes linking climate variables to tree-ring formation. A new block of the model allows to estimate a cell production in tree rings and transfer it into time scale based on simulated integral growth rates of the model. The obtained detailed approach with a calculation of time moment of each cell formation improves significantly the date accuracy of new cell formation in growing season. In the developed algorithm we used integral growth rates simulated by the VS-model for each growing season. The approach was applied and tested for the cell measurements obtained for Scots pine (Pinus sylvestris L.) over the 1964-2009 in the middle stream flow of Malaya Minusa river (Khakassia, Southern Siberia). [ABSTRACT FROM AUTHOR]

Tree-ring records are annually resolved, well replicated, and can be calibrated and validated against the instrumental record. We analyze relationships between climate and tree-ring data using the VS-Oscilloscope (parameterization software of process-based tree-ring Vaganov-Shashkin model). The obtained approach can provide useful data to better understand how tree growth there is controlled by climate conditions. Scots Pine (Pinus sylvestris) was selected as a tree species in the work. Wood samples were collected at the site in 25 km distance from meteorological station "Minusinsk", southern Siberia. The key goals of the study are: to assess a performance of the VS-Oscilloscope on semiarid territories; to obtain "optimal" tree-ring growth parameters during the calibration time interval and check them for the verification period; and to understand how climate principal factors can affect on ring formation, to evaluate differences in climate forcing on tree-ring growth between growing seasons when wide and narrow rings were formed. Simulated tree-ring growth indexes significantly correlate to initial tree-ring chronology. Outputs of the modeling demonstrates that start and end of growth season are influenced by temperature, while rest period of growth is limited by precipitation. That fact confirmed by natural field observations. Moreover the analysis of specific growing seasons when wide and narrow rings were formed show us how daily rainfall and temperature affect on tree-ring growth rate for particular years. The Lazarus Code of the VS-oscilloscope and distributive package (free usinglicense) can be downloaded from the http://vs-genn.ru/downloads/. Technical questions can be addressed to Ivan Tychkov: ivan.tychkov@gmail.com. The work was supported by the Russian Science Foundation (RSF project # 14-14- 00219). [ABSTRACT FROM AUTHOR]