Late-Holocene palaeoecological reconstruction of Southern Hemisphere Westerlies variability on Subantarctic Macquarie Island

A detailed reconstruction of Southern Hemisphere Westerlies (SHW) variability over the last 2500 years on Macquarie Island reveals periods of strengthened and weakened westerly winds, linked to changes in sea spray-driven lake conductivity. The study found that stronger SHW occurred around ~2500–2300 cal. yr BP and after ~800 cal. yr BP, while weaker SHW prevailed between ~2300–800 cal. yr BP. These findings were derived from palaeoecological analysis of halophilic and halophobic diatoms preserved in lake sediments, which correlate with water conductivity gradients influenced by westerly winds. The study provides a critical long-term record of SHW behavior, offering insights into past atmospheric CO2 concentrations and Southern Hemisphere climate dynamics.

Deng, Y. N., Roberts, S. J., Saunders, K. M., Perren, B., & Selfe, C. (2026). Late-Holocene palaeoecological reconstruction of Southern Hemisphere Westerlies variability on Subantarctic Macquarie Island. The Holocene, 36(7), 693–706. https://doi.org/10.1177/09596836261432461