Developing an Absolutely-Dated Holocene Tree-Ring Chronologyfrom Sub-Fossil Huon Pine in Tasmania for Paleoclimate and Isotopic Studies

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This is a 2 year project aimed towards developing a continuous, absolutely dated Holocene tree-ring chronology from live and sub-fossil huon pine located in western Tasmania, Australia. Based on the known ages of sampled living trees (1000 years old) and a series of overlapping radiocarbon dates from recovered sub-fossil logs, all from the Stanley River in western Tasmania, tree-ring specimens are in hand for developing a chronology almost 3000 years in length. In addition, other sub- fossil logs recovered from deposits at the Stanley River have radiocarbon dates that extend back beyond the present radiocarbon calibration curve derived from Northern Hemisphere trees. Consequently, there is the proven potential for a 9-10,000 year tree-ring chronology from Tasmania that would include the climatically interesting Hypsithermal warm period (ca. 7-9,000 BP), with the realistic prospect of it eventually extending back to the Younger Dryas cold event (ca. 10-11,000 BP) and the glacial- interglacial transition (ca. 13-14,000 BP). We will exploit to the fullest extent possible the Stanley River sub-fossil wood now in hand, sample additional logs from that locality, and explore Tasmania for other huon pine sites in an effort to locate pre-9,000 BP wood for extending the radiocarbon calibration curve. In the process, we will also develop a network of 1000 year long modern tree-ring chronologies for Tasmania and, if possible, New Zealand that will be used to reconstruct past climate in that sector. The precisely dated wood produced by this project will be available for other scientific studies, including stable isotope and carbon-14 analyses, in order to make this project as scientifically productive as possible.