Possibility of identification of negative extreme climatic events using Pinus sylvestris tree-rings in Transdanubia, Hungary

Abstract

Negative climatic extremes occur more frequently in the last decades. Since the Carpathian Basin is highly concerned in their impacts it is important to investigate prior events and estimate the response of the environment to them to get useful information for the future. In our work we selected a stand which is seriously affected by unfavorable summer conditions to examine what kind of fingerprint the negative extreme events have left. We investigated narrow rings and intra-annual density fluctuation to describe years with extreme events. Their stabilized frequency was tested against climatic and groundwater data, as well as against aridity index to determine climate-growth relationships using Pearson and Spearman’s correlations. Our results show positive significant correspondence between summer precipitation and tree-ring growth together with negative connection with summer temperature. The Spearman’s correlation between stabilized frequency of intra-annual density fluctuations, narrow rings and climate data ended with significant relationship in summer. According to the comparison of intra-annual density fluctuation and narrow ring data with drought periods it can be said that narrow rings are better tool for the examination of negative extreme events in summer.