A new report, published in the journal Environmental Research Letters, finds that 1200 years of volcanic activity was chronicled in the texts of irish monks. The report was the work of an international team led by Dr Francis Ludlow from Harvard University.
Ludlow's team compared ice core data from the Greenland Ice Sheet Project with the Irish Annals, manuscripts in which "scribes recorded significant events such as feast days, obituaries and descriptions of extreme cold and heat." The team found that the monks recorded 37 or 38 volcanic eruptions. "These eruptions occur and they override existing climate patterns for a period of two or three years," said Dr Ludlow.
An abstract of the paper is available online.