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High-resolution palaeoclimate proxies are fundamental to our understanding of the diverse climatic history of the Australian mainland, particularly given the deficiency in instrumental datasets spanning more than a century. Annually resolved, tree-ring-based proxies play a unique role in addressing limitations in our knowledge of interannual to multi-decadal temperature and hydroclimatic variability prior to the instrumental period. Here we present cross-dated ring-width (RW) and minimum blue-intensity (BI) chronologies spanning 70 years (1929–1998) for Podocarpus lawrencei Hook.f., the Australian mainland's only alpine conifer, based on nine full-disc cross-sections from Mount Loch in the Victorian Alps. Correlations with climate variables from observation stations and gridded data across the 1929–1998 period reveal a significant positive relationship between RW and mean monthly maximum temperatures in winter throughout central Victoria (r=0.62, p<0.001) and a significant negative correlation to winter precipitation (r=-0.51, p<0.001). We also found significant negative correlations between RW and monthly snow depth at Spencer Creek in New South Wales (r=-0.60, p<0.001). Of the assessed BI parameters, delta blue intensity (ΔBI; the difference between early- and late-wood BI) displayed the greatest sensitivity to climate, with robust spatial correlations with mean October to December maximum and minimum monthly temperatures (r=-0.43, p<0.001; r=-0.51, p<0.001) and July precipitation (r=0.44, p<0.001), across large areas of northern Victoria. These promising findings highlight the utility of this species for future work. With the very limited availability of suitable long-lived and cross-datable species on the Australian mainland, these results have significant implications for advancing high-resolution palaeoclimate science in southeastern Australia and for improving our understanding of past climate in the region.

Item Type:	Refereed Article
Keywords:	Podocaprus lawrenicii, southeastern Australia, climate signal
Research Division:	Earth Sciences
Research Group:	Physical geography and environmental geoscience
Research Field:	Palaeoclimatology
Objective Division:	Environmental Policy, Climate Change and Natural Hazards
Objective Group:	Understanding climate change
Objective Field:	Climate variability (excl. social impacts)
UTAS Author:	Allen, KJ (Dr Kathy Allen)
ID Code:	154619
Year Published:	2022
Funding Support:	Australian Research Council (FT200100102)
Deposited By:	Geography and Spatial Science
Deposited On:	2022-12-16
Last Modified:	2022-12-16
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