A new worldwide chronology of volcanic eruptions. (With a summary of historical ash-producing activity and some implications for climatic trends of the last one hundred years)

A chronological enumeration of volcanic eruptions from around the world is used to describe temporal and spatial variations in historical volcanism. Over 5000 eruptions from 907 active volcanoes of the world are classified on the basis of eruption type and scaled on the basis of relative magnitude of ejected material. The chronology extends from 2227 B.C. to 1969 A.D. but is most reliable after 1850 A.D. Advantages of the data set over other existing chronologies include a vastly increased sample size, a scheme for assessing the relative ash-producing magnitude of each eruption, and a computerized data-storage format. Preliminary application of the eruption chronology to global and hemispheric temperature trends for the period 1880-1969 demonstrates that episodes of frequent and intense ash-producing eruptions tend to be associated with periods of cooler hemispheric temperatures, while volcanically quiescent episodes tend to correspond with periods of hemispheric warming.