A possible link between Sun's variability and volcanic activity

Abstract

Sun inconstancy has the ability to control global climate, that in turn acts as a trigger for volcanic activity. Looking for possible Sun-Earth connections we analysed the time distribution of eruptions of volcanoes located on the northern hemisphere, from the Caribbean Sea to the East Mediterranean Sea, with a particular detail on the most active Italian volcanoes. The compared analysis between sunspot and volcanic cycles suggested that volcanic eruptions are more frequent during minima of Sun activity, with about 3 eruptions out of 4 occurring at relative minima of the quasi-11 year Sun cycle. Not so evident are the long term (centennial time scale) relationships between Sun and volcanic system variability: since the former is controlled by much more complex mechanisms the analysis of correlations between eruptions and Sun activity cannot prescind from geodynamical discriminants, which play a fundamental role in driving magma migration toward the Earth’s surface.