How volcanoes upend the story of what sparked the Black Death

"The paper in the journal Communications Earth & Environment is the latest in a wave of recent scientific and historical evidence that is rewriting our understanding of the bubonic plague pandemic that tore across medieval Europe, killing more than half of the people it infected, more than half a millennium ago. The plague is transmitted by insects that feed on blood, such as fleas, and usually cycles through rodent populations - but has jumped into humans, sparking three deadly pandemics that killed millions."

"Martin Bauch, a medievalhistorian at the Leibniz Institute for the History and Culture of Eastern Europe and Ulf Büntgen, an environmental systems scientist who studies tree rings to understand the past climate at the University of Cambridge, teamed up to reexamine data from ice cores, unusual tree rings and historical records to reconstruct a different narrative rooted in a chain of interconnected environmental and societal events."

Ice cores, tree rings and historical records indicate volcanic eruptions around 1345 spewed sulfur into the atmosphere, triggering a climate downturn across Europe. Cooler summers and increased rainfall impaired harvests, leading to widespread crop failures and famine. Medieval trade networks and maritime travel facilitated disease movement between regions already weakened by food shortages. The bubonic plague, transmitted by blood-feeding insects such as fleas and cycling in rodent populations, jumped into human populations and caused catastrophic pandemics. Cross-disciplinary evidence reconstructs a chain of environmental stressors and societal vulnerability that precipitated the mid-14th century Black Death.

Read at The Washington Post