Dendroclimatic Analysis of Birch in South Greenland

Abstract

Dendrochronological research in Greenland has met with only qualified success in the last two decades, and no dendroclimatic interpretations have resulted from these initial efforts. During the summer of 1978, field work was conducted on stands of birch (Betula pubescens) in a uniquely fertile and isolated valley, Qinguadalen (60?16'N, 40?30'W). Although the birch suffer considerable geomorphic stress, conventional dendroclimatic procedures revealed significant growth response to climate. Trees generally exhibit contorted or near-horizontal stems, producing asymmetry in the pith-to-bark dimensions, and frequently develop heart-rot. Of the 35 trees sampled, the oldest datable stem was 143 yr old. A growth response function derived from multivariate analysis of the chronology and 35 yr of climatic (principal component) data from Ivigtut relates 38% of the chronology variance to climate and a total of 60% to climate plus prior growth. Although the Qinguadalen birch chronology is relatively short, it does contain considerable information concerning the relationship between climatic variables and tree growth for the region.