Tree-ring width and blue intensity chronologies of three co-existing conifer species from the Russian Altai mountains reveal different climate signals

Abstract

The Altai in southern Siberia is one of the few mid-latitude mountain ranges where summer temperatures have been reconstructed over the past 2000 years. While tree-ring width (TRW) measurements have traditionally been used, the paleoclimatic potential of more advanced wood density parameters from different tree species remains largely unexplored in this region. Here, we examine the climatic response of three co-existing conifer species (Larix sibirica Ledeb., Pinus sibirica Du Tour and Picea obovata Ledeb.) from the Russian Altai at ∼1600 m a.s.l. We develop TRW, latewood blue intensity (LWBI), and delta blue intensity (DBI) chronologies, and compare them against monthly temperature means and precipitation totals over the 1951–2021 period. Our results show that all three species respond positively to summer temperatures. The LWBI and DBI chronologies exhibit stronger and more consistent summer temperature signals than TRW, with the highest correlations found in P. obovata (r = 0.7) and P. sibirica (r = 0.5). Despite species-specific differences in temperature sensitivity, our findings demonstrate the potential of LWBI and DBI for robust summer temperature reconstructions in inner Eurasia.