Abstract
Forecasting future destructive eruptions from re-awakening volcanoes remains a challenge, mainly due to a lack of previous event data. This sparks a search for similar volcanoes to provide additional information, especially those with better compiled and understood event records. However, we show that some of the most obviously geologically comparable volcanoes have differing statistical occurrence patterns. Using such matches produces large forecasting uncertainties. We created a statistical tool to identify and test the compatibility of potential analogue volcanoes based on repose-time characteristics from world-wide datasets. Selecting analogue volcanoes with compatible behaviour for factors being forecast, such as repose time, significantly reduces forecasting uncertainties. Sensitivity tests show that this method is robust to the problem of missing data. We will illustrate this method by applying it to Tongariro and Taranaki volcanoes (NZ) and analogues obtained from the GVP catalogue.