Study for the periodicity of volcanic activity using satellite data

Some volcanoes show a kind of periodicity through the time series of volcano temperature. Analyzing the satellite data observed in 2012 from 2006, there are found six volcanoes in which the high temperature occurs in a periodic interval from half year to two years. The activity pattern appears like some kind of pulse train. There is a possibility of the periodical event which occurs according to the characteristic cause belonging to individual volcano. The pulse train of the Bezymianny volcanic activity from 1955 to present was studied in detail. A short period like 15 months is found. However then, what is a large event excluded from the periodic event? Is it an event in a long periodicity related with the crustal movement of the Earth? The authors make a guess at a model of the volcanic activity that actual volcanic activity appears as a result of adding a few kinds of the pulse trains by each different cause. It is a kind of energy discharge pattern with some continuous energy supply typically seen in a geyser at the Yellow Stone National Park in U.S.