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The Southern Hemisphere westerly winds (SWW), a belt of strong zonal winds in the mid-latitudes, play a key role in Southern Hemisphere climate variability. Recent intensification and southwards migration of the SWW is projected to continue due to anthropogenic climate change and despite a recovering Antarctic ozone hole, impacting regional hydroclimate, ocean circulation and carbon cycling. Despite the importance of the SWW, our understanding of their behaviour on centennial to millennial timescales is limited by the inherently short observational record and limited palaeo-archive agreement on the wind belt's Holocene dynamics. Here we utilise dust flux, Itrax core scanning, rare earth element composition and HYSPLIT particle modelling to present a 8700-year (10,500–1700 cal yr BP) reconstruction of local SWW intensity from a Falkland Islands (Islas Malvinas) peat sediment core which, along with other reconstructions, we interpret in a regional South Atlantic and hemispheric context. We find increased dust deposition and variability from ca. 5700 cal yr BP, signalling an intensification and possible southwards shift of the SWW, though Patagonia likely remains the primary distal dust source throughout our record. Additionally, we identify asymmetric behaviour in the SWW belt from 3000 to 1700 cal yr BP over southern South America and the southwest Atlantic. In alignment with these findings, we propose a possible eastwards projection of the Amundsen Sea Low (ASL) into the South Atlantic during this period. Two volcanic eruptions, likely from Mt Burney (ca. 9700 cal yr BP) and Mt Hudson (ca. 4100 cal yr BP), are captured as cryptotephra deposits in the record. Our precisely dated, high-resolution multiproxy record of South Atlantic wind-blown transport provides an important new dataset that accurately constrains SWW Holocene variability over the Falkland Islands.

The authors regret that the printed version of the above article contained a transcription error in the m/z 1048 peak area column for the branched GDGTs (Table S2). This error affected the GDGT-inferred summer air temperature presented in Figs. 3, 4 and 5, and some of the calibrations presented Fig. S2. The GDGT-inferred temperatures have been recalculated and are presented below. The authors would like to apologise for any inconvenience caused. The corrected GDGT-inferred summer air temperature (Fig. 3) is largely within the uncertainty of the temperature calibration (2.0 °C RMSE, Pearson et al., 2011). While the pattern of the temperature variations over the last 3500 years remains unchanged, the GDGT-inferred summer air temperature is between 0.4 and 3.3 degrees lower than was originally presented. The interpretations of Thomas et al. (2022) are unaffected, with reconstructed changes in temperature at Club Lake still associated with several other palaeoenvironmental proxies. Section 4.1 “Our reconstruction of MSAT varies between about 13 and 16 °C, and appears to display a long-term increase in temperature averaging ~0.1 °C per century (Fig. 3).” should be “Our reconstruction of MSAT varies between about 10 and 15 °C, and appears to display a long-term increase in temperature averaging ~0.13 °C per century (Fig. 3).” Section 4.2 “The reconstructed temperature of 16.2 ± 1 °C (which is higher than the contemporary Thredbo AWS mean summer temperature) must therefore be treated with caution.” should be “The reconstructed temperature of 15.7 ± 1 °C (which is higher than the contemporary Thredbo AWS mean summer temperature) must therefore be treated with caution.” The updated figures and Supplementary information table and figure related to this corrigendum are presented below. [Figure presented] [Figure presented] [Figure presented]

Wetland sediments are valuable archives of environmental change but can be challenging to date. Terrestrial macrofossils are often sparse, resulting in radiocarbon (14C) dating of less desirable organic fractions. An alternative approach for capturing changes in atmospheric 14C is the use of terrestrial microfossils. We 14C date pollen microfossils from two Australian wetland sediment sequences and compare these to ages from other sediment fractions (n = 56). For the Holocene Lake Werri Berri record, pollen 14C ages are consistent with 14C ages on bulk sediment and humic acids (n = 14), whilst Stable Polycyclic Aromatic Carbon (SPAC) 14C ages (n = 4) are significantly younger. For Welsby Lagoon, pollen concentrate 14C ages (n = 21) provide a stratigraphically coherent sequence back to 50 ka BP. 14C ages from humic acid and >100 µm fractions (n = 13) are inconsistent, and often substantially younger than pollen ages. Our comparison of Bayesian age-depth models, developed in Oxcal, Bacon and Undatable, highlight the strengths and weaknesses of the different programs for straightforward and more complex chrono-stratigraphic records. All models display broad similarities but differences in modeled age-uncertainty, particularly when age constraints are sparse. Intensive dating of wetland sequences improves the identification of outliers and generation of robust age models, regardless of program used.

The alpine area of the Australian mainland is highly sensitive to climate and environmental change, and potentially vulnerable to ecosystem tipping points. Over the next two decades the Australian alpine region is predicted to experience temperature increases of at least 1 °C, coupled with a substantial decrease in snow cover. Extending the short instrumental record in these regions is imperative to put future change into context, and potentially provide analogues of warming. We reconstructed past temperatures, using a lipid biomarker palaeothermometer technique and mercury flux changes for the past 3500 years from the sediments of Club Lake, a high-altitude alpine tarn in the Snowy Mountains, southeastern Australia. Using a multi-proxy framework, including pollen and charcoal analyses, high-resolution geochemistry, and ancient microbial community composition, supported by high-resolution 210Pb and AMS 14C dating, we investigated local and regional ecological and environmental changes occurring in response to changes in temperature. We find the region experienced a general warming trend over the last 3500 years, with a pronounced climate anomaly occurring between 1000 and 1600 cal yrs. BP. Shifts in vegetation took place during this warm period, characterised by a decline in alpine species and an increase in open woodland taxa which co-occurred with an increase in regional fire activity. Given the narrow altitudinal band of Australian alpine vegetation, any future warming has the potential to result in the extinction of alpine species, including several endemic to the area, as treelines are driven to higher elevations. These findings suggest ongoing conservation efforts will be needed to protect the vulnerable alpine environments from the combined threats of climate changes, fire and invasive species.

The timing and duration of the coldest period in the last glacial stage, often referred to as the last glacial maximum (LGM), has been observed to vary spatially and temporally. In Australia, this period is characterised by colder, and in some places more arid, climates than today. We applied Monte-Carlo change point analysis to all available continuous proxy records covering this period, primarily pollen records, from across Australia (n = 37) to assess this change. We find a significant change point occurred (within uncertainty) at 28.6 ± 2.8 ka in 25 records. We interpret this change as a shift to cooler climates, associated with a widespread decline in biological productivity. An additional change point occurred at 17.7 ± 2.2 ka in 24 records. We interpret this change as a shift towards warmer climates, associated with increased biological productivity. We broadly characterise the period between 28.6 (± 2.8) – 17.7 (± 2.2) ka as an extended period of maximum cooling, with low productivity vegetation that may have occurred as a combined response to reduced temperatures, lower moisture availability and atmospheric CO2. These results have implications for how the spatial and temporal coherence of climate change, in this case during the LGM, can be best interrogated and interpreted.

The Chronos 14Carbon-Cycle Facility is a new radiocarbon laboratory at the University of New South Wales, Australia. Built around an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) Accelerator Mass Spectrometer (AMS) installed in October 2019, the facility was established to address major challenges in the Earth, Environmental and Archaeological sciences. Here we report an overview of the Chronos facility, the pretreatment methods currently employed (bones, carbonates, peat, pollen, charcoal, and wood) and results of radiocarbon and stable isotope measurements undertaken on a wide range of sample types. Measurements on international standards, known-age and blank samples demonstrate the facility is capable of measuring 14C samples from the Anthropocene back to nearly 50,000 years ago. Future work will focus on improving our understanding of the Earth system and managing resources in a future warmer world.