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A near-continuous, highly dynamic record of Silurian climate has been determined from conodont δ¹⁸O compositions (δ¹⁸O_phos), representing stratigraphic sections from four palaeocontinents. Following the late Ordovician–early Silurian glaciation, numerous small-scale climate cycles show an overall warming trend until the mid Llandovery (early-mid Telychian), then gradual cooling through the late Llandovery. Two major, multi-step cooling transitions of similar magnitude and duration (+ 2‰ within ~ 1.5 Myrs from onset to peak) occurred during the late Llandovery–early Wenlock and late Wenlock, the former culminating in a prolonged cool interval (~ 1 Myr). These Wenlock δ¹⁸O_phos excursions coincided closely with the Ireviken and Mulde biotic and carbon isotope (δ¹³C) events. Rapid, large, but short-lived shifts reflect climate instability within the mid Ludlow, prior to and during the Lau bio-event. The prime …