| Summary: | Inter annual or inter decadal climate reconstructions in the subarctic region and in high-mountain environments suffer from the absence of suitable long instrumental climate records. Annual tree-rings, along with other annually resolved natural archives, are widely used as proxies in high resolution paleoclimatology. A temperature signal-loss has been reported in tree-rings width and density records from several temperature-limited environments since the mid-20th century, revealing a decreasing attitude of tree-ring parameters in tracking increasing instrumental temperatures. In this study we carried out a dendroclimatic analysis on a data set of five European larch ring-width chronologies in the Adamello-Presanella Group, in the Italian Central Alps. We intended to evaluate the dendroclimatic potential of the high-elevation conifer vegetation to be used as a climate proxy, assessing the stability over time of the climate/tree-ring growth relationship. The dendroclimatic analysis was performed by means of correlation function and response function analysis, which allowed identifying climate parameters mainly involved in tree-rings growth. For capturing the dynamical variability of climate signal in the five tree-ring width chronologies, and to verify the stability over time of tree-rings/climate relationship, moving correlation function and moving response function analysis have been used. Moreover, to test the efficiency of the tree-rings dataset for climate reconstruction purposes, we conducted a reconstruction of JJ temperature for the 1596-2004 time period. The analysis of climate/tree ring growth relationships, producing results that are consistent with the more recent dendroclimatic studies in the Alpine Region, confirmed the presence of a common climatic signal for conifers living at the timberline ecotone. From the monthly climatic analysis a strong positive influence of early summer (JJ) temperatures on the tree growth emerged, with June mean temperature showing the highest positive correlation. ...
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