A tree-ring densitometric transect from Alaska to Labrador

Abstract

We describe a recently completed network of densitometric tree-ring time series representing various aspects of tree-growth for up to 200 years at 69 sites spread across the northern North American conifer zone from Yukon to Labrador. Duplicate cores, from 12 to 15 trees per site, provide time series for a suite of growth parameters including earlywood (spring), latewood (summer) and total (annual) ring widths and mean earlywood, mean latewood, minimum and maximum ring density. These data form the basis for extensive analyses of intra- and inter-site parameter comparisons and regional climate/tree-growth comparisons. Five large-scale regional chronologies do not suggest that any anomalous growth increases have occurred in recent decades, at least on these regional scales, despite the observed changes in atmospheric composition and climate.