While paleoclimatic studies have extended our understanding of North Pacific climate variability, these have been almost exclusively based on proxies from western North America. We present a tree-ring reconstruction of June to September coastal air temperatures for Nemuro, northeastern Japan for the past four centuries. It explains 36% of the variance in instrumental temperatures and correlates significantly with indices of the atmosphere–ocean circulation. Spectral analyses reveal robust bidecadal peaks that appear associated with regional modes of western North Pacific variability. At decadal time scales, Nemuro temperatures appear to be influenced by the confluence of the Kuroshio and Oyashio currents, a primary centre of action driving Pacific Decadal Variability. Regime shifts (e.g. 1976) are weakly expressed relative to western North America. These aspects of western North Pacific climate are regionally distinct relative to those elsewhere in the basin, with greater complexity than can be attributed to the Pacific Decadal Oscillation (PDO) alone.

The data set presented represents 15 years of collection. It contains tree-ring width measurements from 64 sites of living trees and ten historical chronologies based on archaeological and construction wood up to year 572 CE, altogether 2909 tree-ring series and more than 450000 measured and cross-dated tree rings. It covers the vast territory of European Russia, including its forested northern and central parts, and the Northern Caucasus mountains. The potential use of these data include climatic reconstructions of regional and hemispheric scale, dendrochronological dating of historical and cultural wood, ecological and remote sensing studies.

Variability of width, maximum density and stable isotopes (δ¹³C) in tree-rings of Scots pine (Pinus sylvestris L.) were studied in Northern Caucasus. Statistically sufficient agreements between ring width chronologies allow to construct composite chronology for the Elbrus area. Absence or low correlation between indices of the ring width and maximum density chronology point out different climatic signal. The influence of temperature and precipitation on these tree-ring parameters was also analyzed. The ring width of pine at the upper tree limit in the Baksan valley correlates positively with the June and July precipitation (r=0.3; 0.3; 0.4, p<0.05). No correlation with temperature parameters was found. The maximum density reflects the warm period temperature (April-October). The similarity in interannual variations of δ¹³C in annual rings between the individual samples means that their display a coherent common signal. This signal can be largely interpreted as the June and July precipitation.