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Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850–2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.

Although tree-ring-width chronologies have been widely used for temperature reconstructions, there are many sites around the world at which there is little evidence of a clear climate signal in the ring-width chronologies. This is the case with the long-lived conifer Huon pine (Lagarostrobos franklinii (Hook. F.) Quinn), endemic to Tasmania, Australia, when the species grows at low elevation. In this study, we developed chronologies of several wood properties (e.g., tracheid radial diameter, microfibril angle) from Huon pine growing at a low-elevation site. We found that despite the absence of a climate signal in the ring-width chronologies, there were significant correlations between wood density, tracheid radial diameter and microfibril angle and temperature, stream flow and a drought index, enabling the development of robust chronologies. This novel finding suggests that chronologies based on these wood properties may have important potential for climate reconstructions from sites and species that have not yet been realized. In particular, a relatively extensive resource of ancient, low-elevation Huon pine in western Tasmania, in which climate signals have not been found using ring widths, may now be useful as part of the broader effort to reconstruct Southern Hemisphere climate.

Abstract. Australian seasonal rainfall is strongly affected by large-scale ocean-atmosphere climate influences. In this study, we exploit the links between these precipitation influences, regional rainfall variations, and palaeoclimate proxies in the region to reconstruct Australian regional rainfall between four and eight centuries into the past. We use an extensive network of palaeoclimate records from the Southern Hemisphere to reconstruct cool (April-September) and warm (October-March) season rainfall in eight natural resource management (NRM) regions spanning the Australian continent. Our bi-seasonal rainfall reconstruction aligns well with independent early documentary sources and existing reconstructions. Critically, this reconstruction allows us, for the first time, to place recent observations at a bi-seasonal temporal resolution into a pre-instrumental context, across the entire continent of Australia. We find that recent 30-and 50-year trends towards wetter conditions in tropical northern Australia are highly unusual in the multi-century context of our reconstruction. Recent cool-season drying trends in parts of southern Australia are very unusual, although not unprecedented, across the multi-century context. We also use our reconstruction to investigate the spatial and temporal extent of historical drought events. Our reconstruction reveals that the spatial extent and duration of the Millennium