The team also tracked down 13 narrative accounts of adverse weather, crop failure and famine from that time period, further supporting the theory that a series of eruptions had slammed Europe's climate. The rings, which change thickness in response to climate patterns, revealed that 1109 was an unusually cold, wet year in Western Europe - a climatic 'anomaly' comparable to the effects of several other major volcanic eruptions from history, the researchers said. The team found further evidence of volcanic activity in tree rings dating from the same period. 1110, suggesting that the stratosphere was sprinkled with fumes from a recent eruption. The team saw an increase in sulfate aerosols (a component of volcanic ash) in both cores between A.D. Hunting for the 'forgotten'įor evidence of these 'forgotten' eruptions, the researchers looked at ice cores from Greenland and Antarctica - long tubes of ancient ice that can reveal what the global climate looked like at the time, as well as what sorts of particles were floating around in the atmosphere. One such eruption, which occurred in Japan in A.D.

Not only could a high-altitude veil of volcanic aerosols blot out the moon while leaving many stars unobscured, as the Peterborough writer described, but a series of large eruptions could have also disrupted the global climate, the researcher wrote, causing or exacerbated the cold, wet weather that made life so miserable in A.D. Those volcanic events, which the researchers call a 'forgotten cluster' of eruptions because they were sparsely documented by historians at the time, may have released towering clouds of ash that traveled far around the world for years on end. 'Careful evaluation of ice core records points to the occurrence of several closely spaced volcanic eruptions,' which may have occurred in Europe or Asia between A.D. 'The spectacular atmospheric optical phenomena associated with high-altitude volcanic aerosols have caught the attention of chroniclers since ancient times,' the study authors wrote.

The disappearing earth