Changes in sea surface temperatures and dust input at the Lord Howe Rise (Tasman Sea) over the past 580

Sediment core SO290-33-2 from the Lord Howe Rise (Tasman Sea) provides a unique archive to investigate long-term changes in sea surface temperatures (SST) and aeolian dust input from Australia over multiple glacial–interglacial cycles. Owing to its location outside major fluvial influence from New Zealand and Australia, the sediment record is dominated by biogenic carbonate, with minor climatically sensitive terrigenous contributions.

The age model is based on benthic foraminiferal δ¹⁸O stratigraphy, allowing identification of nearly all Marine Isotope Stages back to ~580 ka. Sedimentation rates range from ~0.5 to 2.2 cm kyr⁻¹.

Alkenone-based SST reconstructions reveal pronounced glacial–interglacial variability with amplitudes of ~5–6 °C, particularly after the Mid-Brunhes Transition. Interglacial SSTs average ~24 °C, with peak values of up to 25 °C during the last interglacial (MIS 5e), while glacial minima reach ~17 °C during MIS 10. The pattern of SST variability broadly resembles temperature changes recorded in the EPICA Dome C ice core, although reduced pre–Mid-Brunhes amplitudes reflect relatively warm glacials rather than cooler interglacials (as documented in the ice core).

Dust input is assessed using n-alkane mass accumulation rates and lithogenic content derived from XRF core-scanner dataand geochemical calibrations. Both proxies show enhanced dust fluxes during glacial periods and closely follow Antarctic ice-core dust records, supporting an Australian aeolian origin for terrigenous material at the site. Compared to Subantarctic South Pacific records, glacial dust fluxes at the Lord Howe Rise are lower, likely reflecting its location near the northern margin of major Australian dust source regions, whereas more distal Pacific sites integrate dust input from multiple sources within and outside of Australia.