Geochemical and granulometric fingerprints of 8,200-year Westerly variability recorded in inner-fjord lake sediments from Central Svalbard

Zofia Stachowska , Willem G. M. van der Bilt, Jan Kavan, Mark F. A. Furze, Ingunn H. Thorseth, Mateusz C. Strzelecki

The Arctic is warming faster than any other region on Earth. As sea-ice diminishes, surface boundary conditions (roughness and air-sea coupling) change and open-water fetch increases, potentially strengthening the effective wind forcing on Arctic coasts. These changes can be recorded in lake sediments through the deposition of wind-blown grains and elements, offering insights into past wind and climate dynamics. We reconstruct ca. 8,200 yrs of wind-climate variability using laminated sediments from a closed-basin lake in the Central part of the High Arctic Svalbard archipelago. By integrating geochemical, visual, and granulometric fingerprints within a multiproxy geostatistical framework, we link wind-blown minerogenic input to specific catchment sources and show that iron (Fe)- and titanium (Ti)- enriched clasts originate from distinct dolerite outcrops West of the lake, upwind of the dominant summer Westerlies. These results reveal a locally filtered Westerly input, consistent with valley-fjord channelling. We identify four Mid- and Late Holocene phases of enhanced eolian activity that occurred during intervals when local boundary conditions favoured the entrainment and transport of sediment into the basin. Unit-scale sedimentation shifts can be placed at the end of the Holocene optimum and at the stepwise onset of the Neoglacial. However, the reconstructed wind signal shows comparatively stable long-term behaviour and no direct correspondence with paleoclimate records.