Last Glacial Maximum and deglacial branched GDGT‐based palaeotemperature reconstruction from a subtropical Australian wetland

A palaeotemperature reconstruction from Broutha Waterhole, a subtropical wetland on Fraser Island (K’gari), reveals a temperature minimum of 17.0°C during the Last Glacial Maximum (LGM), with maximum cooling reaching ~4.3°C. This finding aligns with Australia-wide trends and provides a rare quantitative record in the subtropics. The study used glycerol dialkyl glycerol tetraethers (GDGT) to analyze sediment cores, capturing a progressive warming trend during deglaciation, interrupted by a 0.8°C–1.6°C cooling event coinciding with the Antarctic Cold Reversal (ACR). The research highlights regional variability in sediment deposition and contributes critical data to understand past climate dynamics in sensitive wetland ecosystems, offering insights for future projections of subtropical warming and drying.

Macalalad, J., Welsh, K., Hofmann, H., Jacobsen, G., Ni, Z., & Zhang, E. (2025). Last Glacial Maximum and deglacial branched GDGT‐based palaeotemperature reconstruction from a subtropical Australian wetland. Journal of Quaternary Science, 40(8), 1421–1436. Portico. https://doi.org/10.1002/jqs.70017