Evidence for volcanic forcing of Holocene cold events.

During the Holocene, the climatic stability of the northern hemisphere was intermittently disrupted by centennial-scale cooling events, whose origins remain unclear. Explosive volcanism is a plausible trigger, yet its potential to drive longer-term (centennial-to-millennial) perturbations remains underexplored. Here, we compile records of explosive volcanism, atmospheric sulphate, climate variability, and glacial dynamics over the past ~12,000 years to test the temporal correspondence between major eruptions and abrupt cooling events, and assess mechanisms linking volcanic forcing to prolonged climatic shifts. Over 80% of Holocene glacial advances occurred within chronological uncertainty of at least one large (M ≥ 7) eruption in the northern hemisphere. Monte Carlo simulations confirm that this relationship is non-random (p < 0.01). Combined with evidence for sea ice expansion, Atlantic Ocean circulation weakening, and southward tropical rain belt displacement, our results suggest that volcanic impacts can persist well beyond aerosol lifetimes, emphasizing the need to consider dynamical feedbacks in Earth system responses to eruptions.