The largest volcanic eruption in the last 3,700 years

Scientists have discovered the source of a massive 13th century volcanic eruption: a volcano called Samalas on Indonesia’s Lombok Island. The blast was eight times as powerful as Krakatoa.

Though the eruption was equatorial, its impact was felt and noted around the world. “The climate was disturbed for at least two years after the eruption,” Lavigne said. Evidence of this was found in studies of tree rings that revealed abnormal growth rates, climate models, and historical records from as far afield as Europe.”

Medieval chronicles, for example, describe the summer of 1258 as unseasonably cold, with poor harvests and incessant rains that triggered destructive floods — a “year without a summer.” The winter immediately following the eruption was warmer in western Europe, however, as would be expected from high-sulfur eruptions in the tropics. The team cites historical records from Arras (northern France) that speak of a winter so mild “that frost barely lasted for more than two days,” and even in January 1258 “violets could be observed, and strawberries and apple trees were in blossom.”

Note that at a volume of 40 km³ of debris, Samalas doesn’t even come close to being on the list of the 40 most explosive volcanic eruptions in history, most of which happened millions of years ago. (via digg)

• science
• volcanoes