INVESTIGATION OF THE ANNUAL VARIABILITY OF THE ALEPPO PINE TREE-RINGS WIDTH: THE RELATIONSHIPS WITH THE CLIMATIC CONDITIONS IN THE ATTICA BASIN

The relationships between the annual variability of the Aleppo pine tree-ring widths and the variability of the main climatic parameters in the Attica basin are analysed in the present study for a 45-year period (1959-2003). The Principal Components Analysis was applied to the times-series of the tree-rings indices (12 populations) as well as to the residual time-series of the monthly precipitation, maximum and minimum temperatures derived from 5 meteorological stations located in the study region. The results showed that the 64% of the total variance of the tree-rings of the Aleppo pine could be attributed to the common variability of the climatic parameters: for precipitation with 82.6%, for minimum temperature with 88.2% and for maximum temperature with 88.5% of the total variance of each parameter. Characteristic narrow and wide tree-rings were observed during the hydrological years with extreme rainfall or temperature conditions. Finally the study of the climate growth links, on a local basis, showed that the growth of the Aleppo pine is related positively (positive correlations) with the winter and spring precipitations. On the other hand negative correlations were found with the temperatures of the spring months.