Climate Influence in Dendrochronological Series of Araucaria angustifolia from Campos do Jordão, Brazil

Abstract

A dendrochronological series of Araucaria angustifolia was analyzed for a better understanding of the climatic factors that operate in Campos do Jordão city, São Paulo state, Brazil. The dendroclimatic analysis was carried out using 45 samples from 16 Araucaria angustifolia trees to reconstruct the precipitation and the temperature over the 1803–2012 yearly interval. To this end, Pearson’s correlation was calculated between mean chronology and the climatic time series using a monthly temporal resolution to calibrate our models. We obtained correlations as high as r=0.22(α=0.1) for precipitation (February), and r=0.21(α=0.1) for temperature (March), both corresponding to the end of the summer season. Our results show evidence of temporal instabilities because the correlations for the halves of 1963–2012 were very different, as well as for the full period. To overcome this problem, the dendrochronological series and the climatic data were investigated using the wavelet techniques searching for time-dependent cause–effect relationships. From these analyses, we find a strong influence of the region’s precipitation and temperature on the growth of tree ring widths.

Comparison of El Niño-Southern Oscillation Measurement Parameters Through Its Influences on Tree Growth Rings

“…The Expressed Population Signal (EPS) was also calculated. It measures the proportion of variance of a population in a chronology that can be described by a finite subsample, telling how good the chronology is representing an infinite population (WIGLEY et al, 1984, COOK et al, 1990, (BRIFFA, 1900), in other words, guarantees that not one or a few samples are leading the chronology values (SILVA et al,2021). EPS can be calculated by Equation 2.…”