Dating volcanic eruptions with tree-ring chemistry

Dendrochemical analyses of absolutely dated, overlapping sequences of tree rings allow identification of temporally conscribed, volcanically influenced periods of environmental change. Dendrochemistry, or the study of tree-ring elemental composition, is a promising new technique for reconstructing climate/environmental history at annual resolution. In particular, dendrochemistry may be useful for identifying periods of climatically and/or environmentally effective volcanic activity. Airborne pollution from major volcanic eruptions in the form of increased environmental acidity from sulfur dioxide can cause changes in availability and concentration of certain elements and can increase the availability of those elements in the soil, resulting in increased uptake by trees from the substrate or direct from the atmosphere. In particular, spikes, dips, or major changes in trace element concentration may be an indication of changes in soil or atmospheric chemistry (e.g., Padilla and Anderson 2002).