Tree-ring and summer-temperature response to volcanic aerosol forcing at the northern tree-line, Kola Peninsula, Russia

Potential linkages between volcanic activity and a 403-year record of Pinus sylvestris L. (Scots pine) growth and summer temperatures estimated from tree-ring widths are evaluated from an Arctic tree-line site on the Kola Peninsula, northwestern Russia. The joint occurrence of volcanic eruptions and severe negative ring-width values is more than four times that expected by chance. A composite average of temperatures indicates that a 0.72°C temperature reduction is typical for the year immediately following volcanic eruptions, while tree growth is reduced for up to two decades. The Greenland Ice Sheet Project 2 (GISP2) volcanic sulphate record shows a small but significant correlation with summer temperatures. Volcanic aerosols originating at low and middle latitudes appear to cause the greatest ring-width reduction and cooling.