A continuous multimillennial ring-width chronology in Yamal, northwestern Siberia

Remains of subfossil Siberian larch trees in the Holocene deposits of the Yamal Peninsula (Western Siberia) have been collected in order to develop a continuous. multimillennium tree-ring-width chronology. This work has produced a calendar-age dated 4000-year (2000 BC to AD 1996) series. From these data, summer-temperature variability in this region has been estimated on annual to multidecadal timescales. Radiocarbon dating of selected older material shows that the oldest subfossil wood is 9400 years old and the dates of the sampled material are generally distributed evenly through time. It will, therefore, be possible to develop a tree-ring chronology for more than nine millennia. An initial assessment of long-term fluctuations in Yamal summer warmth has been realized through the reconstruction of tree-line dynamics using a combination of dendrochronological (absolute) dated material and less precisely (radiocarbon) dated older subfossils.