Abrupt global climate disruptions 16,100 years ago due to catastrophic Barents ice dam collapse

An abrupt multi-centennial climate perturbation with a possible decadal-scale onset occurred 16.1 thousand years ago (ka) ka during Heinrich Stadial 1 (HS1) (18.4-14.7 ka). However, the spatial extent, its origin, and underlying driving mechanism remain unresolved. Here, we present a new sub-decadal-resolved stalagmite oxygen-isotope record from Thailand, revealing a rapid, massive drying event at 16.134 ± 0.011 ka that lasted for about 6 centuries. Along with paleoceanographic reconstructions and climate model simulations, our synthesis suggests that the large-scale climate event was likely driven by an abrupt freshwater discharge resulting from the saddle collapse of the Barents Ice Sheet. This sudden breach sourced meltwater from the proglacial lakes east of the Eurasian ice sheet directly into the Nordic Sea, causing this abrupt global climate disruption. Our results highlight how local climate events can generate global consequences, with implications for future Atlantic-driven climate change.