Overview
- The peer‑reviewed analysis synthesizes European tree‑ring records, sulfur spikes in Greenland and Antarctic ice cores, and fourteenth‑century documents to time a major eruption around 1345.
- Cooling and poor harvests across the Mediterranean are documented in 1345–1347, with grain prices spiking and Italian city‑states organizing large‑scale imports to stave off famine.
- Venice and Genoa reopened routes to the northern Black Sea in 1347, and the study posits that fleas carrying Yersinia pestis survived on grain dust and reached their ports with those shipments.
- Early outbreaks clustered in import hubs and along subsequent grain redistribution routes, while grain‑producing centers such as Milan and Rome appear less affected in the initial phase.
- The volcano’s source remains unidentified, and the authors present a “most likely” reconstruction rather than proof, highlighting how climate shocks interacting with trade can elevate pandemic risk.