Response of radial increment variation of Scots pine to temperature, precipitation and soil water content along a latitudinal gradient across Finland and Estonia

•No latitudinal trend was observed in the increment-limiting effect of low temperature.•From north to south, the most influential period of temperature for increment variation shifts earlier.•At the high northern latitudes, high current summer precipitation sum promotes tree growth.•Accurate soil information is required to relate soil water content to tree growth.•High-resolution weather data helps to determine periods when climate most influences radial growth. In the Nordic countries, temperature and precipitation regimes are predicted to change as a result of climate change, which may reduce water availability and thus tree growth. This study presents a spatial approach for analysing variations in the annual radial increments of trees across a latitudinal transect. The aim was to evaluate the importance of daily temperature, precipitation and soil water content as regulators of tree growth across a north-south gradient. Increment cores were collected from living Scots pine (Pinus sylvestris L.) trees growing on dry and sandy soils in five regions in Finland and two regions in Estonia. A total of 1 024 trees were measured across 551 sample plots. No clear latitudinal trend was evident in the magnitude of the correlation between the variations in annual increment and the current summer's temperature, but the time period most strongly related to the increment variation shifted towards earlier dates with a decrease in latitude southwards. Thus, the results challenge the traditional findings that the growth of trees located at lower latitudes is less affected by temperature. Moreover, the results demonstrate the importance of using high-resolution weather data when analysing variations in the radial increments of trees. In all of the regions, including the high northern latitudes, high precipitation in the current summer promotes tree growth, and the correlation between summer precipitation and the increment variation increases with a decrease in latitude. The correlations between increment variation and soil water content estimated using two different models were lower than those involving precipitation. The results suggest that accurate soil information is needed to describe the connection between water content and tree growth.