A 403-Year Record of July Temperatures and Treeline Dynamics of Pinus sylvestris from the Kola Peninsula, Northwest Russia

Abstract

A 403-yr tree-ring chronology (A.D. 1595-1997) was developed from living and dead Pinus sylvestris L. (Scots pine) from near treeline on the Kola Peninsula in northwestern Russia. Ring-width is significantly correlated with mean July temperatures. A reconstruction of mean July temperatures generally parallels similar dendroclimatic reconstructions from northern Fennoscandia. The Kola reconstruction indicates that the early- to mid-20th century experienced an exceptional period of warm summer temperatures. Dendrochronological techniques were used to estimate the timing of establishment and mortality of Pinus sylvestris at the site. Tree recruitment and mortality appear inversely related and episodic, with pulses of recruitment occurring during the late-17th, 18th, and mid- to late-20th centuries. The mid-20th century pine recruitment episode lags several decades behind the initiation of 20th-century summer warming. Analysis of instrumental climate records and pine recruitment suggests a link between warm fall and early spring conditions in the mid-20th century and increased pine regeneration. The results of this study are similar to findings from northern Fennoscandia and extend this pattern of recent climatic variation and associated treeline response eastward into the Kola Peninsula.