Prehistoric Intense Tropical Cyclones in the South Pacific Ocean

Abstract Tropical cyclones in relation to global warming pose an increasing threat to coastal populations and property, highlighting an urgent need for millennial‐scale paleoclimate reconstructions. In this study, we reconstruct an 8500‐year record of tropical cyclone activity, based on sediment cores from a coastal lake in Fiji. Using coarse fraction anomalies (>63 μm) as the primary proxy, 58 intense cyclones have been identified, revealing multi‐centennial periods with enhanced and reduced cyclone activities. Consistent cyclone occurrences are observed across different sites in the South Pacific during the Roman Warm Period, Medieval Climate Anomaly, and Little Ice Age, all coinciding with pronounced El Niño‐ or La Niña‐like conditions, while a zonal seesaw pattern emerges during neutral to moderate ENSO phases. We propose that variations in the position and structure of the South Pacific Convergence Zone modulated by various ENSO phases offer an accurate indicator of long‐term cyclone variability, superior to ENSO indices alone.