ON LONG-TERM INSTRUMENTAL TEMPERATURE RECORDS AND RECONSTRUCTIONS FROM THE EUROPEAN ALPS

The growth rings of trees can serve as a tool for the reconstruction of environmental processes and variations. Pioneering investigations led by Parker Calkin and others in coastal Alaska used tree rings to date glacial fluctuations with up to annual resolution. The signals preserved in combined living and subfossil (e.g., samples preserved in glacial sediments) tree-ring chronologies were additionally used in these studies to infer climatic variations and contribute to the knowledge provided by highly resolved glacial histories.

With a spatial jump, I will present recent and ongoing progress in the understanding of climate variability in Central Europe from a dendroclimatic perspective. Here, in contrast to most parts of the world, the transition from the pre-industrial to modern time period is recorded directly by the long and continuous meteorological measurements. These instrumental records also allow climate proxy data calibration, and perhaps more importantly, verification tests, to be conducted over about 250 years.

I will report on new tree-ring based temperature reconstructions and show proxy-instrumental fits during the lengthy period of overlap. Such comparisons allow the properties (e.g., temporal stability, skillful frequencies) of tree-ring based climate reconstructions to be understood, but also may allow characteristics of instrumental measurements to be inferred. Discussion related to proxy-instrumental discrepancies will address proxy noise, instrumental inhomogeneities, and uncertainties in the amplitude of both measured and reconstructed temperature fluctuations. Efforts described contribute to the improved quantification of regional to hemispheric-scale climate variability over the past millennium.