Regional climatic signals in Scots pine growth with insights into snow and soil associations

We performed climatic assessments of Scots pine growth variations in Finland over recent decades by their tree-ring series and comparing growth variations to those observed in meteorological records. Tree-ring indices showed non-significant growth trends over roughly the past four decades (1972-2007). The observed growth variability was explained by connexions to the mid-summer (July) climate (temperature and, likely, cloudiness) in the north and to the spring (April) soil temperatures in the south. Tree growth was negatively associated with snow depth at the beginning of dormancy (in November, previous to the corresponding growth year) in the south and during the growing season start (May) in the north. Thus, these analyses emphasized the relevance of snow and soil data, which have usually been overlooked in studies of associations between climate and tree-ring changes.