536 AD: the worst year in history

Start writing...Around 1,500 years ago, a significant climate event caused widespread fear. The sun dimmed, and rain that looked like blood fell from the sky. Fine dust clouds enveloped the Earth. For two years, winter gripped the land. This led to drought, famine, and plague. Death swept through, wiping out entire cities. Millions were affected, yet no one understood what was happening.
This mid-6th century catastrophe is a crucial moment in history. It laid the groundwork for the world we live in today. David Keys, a writer, spent five years investigating this global event from his suburban home. He consulted over 80 experts on various topics, such as droughts and ancient wars. Keys explored historical records from the 6th and 7th centuries worldwide. His book reveals the story of a climatic disaster buried in the Dark Ages. He believes this event changed the course of history.
The mystery captured Keys' attention during a 1994 archaeology conference. Dendrochronologist Mike Bailey gave a lecture about unusual tree ring patterns from the mid-6th century. Bailey recognized trees as silent witnesses to weather changes over thousands of years. Each year, trees form new growth layers, evidenced by rings. Wider rings indicate good years, while narrow rings indicate bad years.
Bailey's invention allows scientists to match ring patterns with known dates. Various laboratories in northern Europe have analyzed tree rings, creating a long-term weather record. This meticulous work involves comparing patterns from older trees and historic buildings to compile a complete record of ring widths over time. After 14 years, Bailey documented an extensive record for Irish oaks, allowing scientists to study weather trends for the past 7,500 years.
David Keys traveled to Ireland to see the 6th-century event documented in Bailey's tree rings. Ten years earlier, Bailey found that oak rings narrowed unusually in the mid-6th century. This pattern indicated something significant obstructed tree growth. He discovered evidence across Europe, including Finland, indicating a drop in tree growth around 536. There was a brief recovery in 537 and 538, but growth dropped dramatically again by 542. Overall, a clear pattern emerged from this research.
The climatic catastrophe of the mid-6th century extended beyond Ireland and Finland. Keys reached out to various labs worldwide and found evidence everywhere. In California, tree rings from the Sierra Nevada mountains showed that 535, 536, and 541 were among the worst years in two millennia. Trees in Chile displayed the largest summer growth drop in 1,600 years. Siberia experienced a 20-year decline in tree growth, the most severe in 1,900 years.
The reasons behind the reduced tree growth remained unclear. Possible explanations included darkness, cold, natural pollution, or drought. Bailey examined oak ring cells from 536 AD and found summer cells typically seen in winter. A colleague in Germany showed him oak trees with abnormal growth patterns. In 536, vessel rings were small and scattered throughout the summer, suggesting frost damage.
The worldwide evidence indicated extremely cold weather. Bailey also found archaeological evidence in Ireland supporting this theory. He dated wood from crannogs, wooden island forts built during hostile times, back to the mid-6th century, likely due to climate issues.
Overall, about a decade of bad conditions seemed to start around 536 and last until the mid-540s. Evidence suggested cold temperatures reduced sunlight and caused crop failures. Populations relied heavily on non-agricultural food sources, such as fishing and hunting, leading to struggles. Keys sought out any written accounts from that period.
Meanwhile, the Roman Empire flourished in the 6th century. After being sacked a century earlier, it had a new capital in Constantinople and regained cultural prominence. Keys contacted classical scholars and found significant Roman accounts detailing unusual weather. John of Ephesus, a bishop, reported a darkened sun lasting 18 months, shining only four hours a day.
Another historical account from Italy mentioned a summer without heat and adverse weather conditions. Keys also researched sources from China, Korea, and Japan, finding records linking directly to the darkened sun event. In 540, a Japanese king remarked on the importance of food for survival during this time. An ancient Chinese chronicle noted yellow dust falling like snow.
Keys recognized that this climatic disaster impacted many civilizations. Research continued, narrowing potential causes to three possibilities: an asteroid, a comet, or a volcanic eruption. Scientists studied the atmospheric effects of cosmic collisions, concluding large impacts could cause climate change. Keys consulted an astrophysicist to determine the necessary size for an impact.
For a lasting climate catastrophe, a substantial asteroid or comet impact would be needed. A 4 km asteroid or a 6 km comet could create the desired effects, but no civilization recorded such an event during the 6th century. A search for a corresponding crater found none.