Holocene Rapid (Decades) Multi-Meter Marine Transgressions Attributable to Climatically Driven Antarctic Ice-Collapse Events: Is Another Collapse Imminent?

Higgs, R., 2026. Holocene rapid (decades) multi-meter marine transgressions attributable to climatically driven Antarctic ice-collapse events: Is another collapse imminent? Journal of Coastal Research, 42(1), 196–209. Charlotte (North Carolina), ISSN 0749-0208. The controversial 1961 Fairbridge Curve of Holocene interglacial sea level (SL), showing meter-scale (to ∼5 m) oscillations based on carbon-dated geological index points (SL benchmarks) around the world, is vindicated by recently published syntheses of the literature on (1) Holocene SL, exposing flaws in the assumptions and methods of the many workers who deny oscillations, and (2) English coastal archaeology, its SL significance previously underappreciated, revealing a ∼4 m SL rise that spanned only ∼70 years (AD ∼430–500), equating to Fairbridge's Rottnest transgression (the most recent) but far more tightly dated by dendrochronology, coins, and pottery. This study hypothesizes that Fairbridge-type, large (m), brief (decades) SL rises are due to Antarctic marine ice-cliff instability (MICI) ice-cliff-collapse events. The Rottnest rise is attributed here to a known 12-year Arctic warm spike (probably solar driven) that peaked in AD 402; the 30-year lag (Rottnest began AD ∼430) is interpreted as the delay for downwelling overwarmed Arctic sea-surface water to reach Antarctica by conveyor-belt ocean circulation. Because of anthropogenic global warming, Arctic average temperature since 2005 has continuously exceeded the AD 402 peak and for a longer time (20 vs. 12 years), portending another MICI-driven SL rise, starting by ∼2035 (2005 plus ∼30-year lag), likely to raise SL at least 3 m by ∼2100 by analogy with the Rottnest transgression. Indeed, closely monitored Antarctic glaciers show signs of approaching failure. On the Fairbridge Curve, each SL rise is followed by a SL fall of similar magnitude, suggesting that the fall is intrinsic to the MICI process. [ABSTRACT FROM AUTHOR]