ABSTRACT
There are about 1500 active and potentially active volcanoes on Earth, of which an average of 70 erupt in any given year (Siebert et al., 2010). This subareal volcanism (i.e., that which is not hidden from us beneath the surface of the ocean) is the most obvious and dramatic manifestation of energy loss from Earth’s interior. The impact of volcanism on the Earth and humanity is profound; volcanism provided us with an atmosphere that it has modified ever since (Condie, 2005) and may have influenced the evolution of life on Earth through the role eruptions have played in mass extinctions (Rampino, 2010). Volcanism has been a source of myth (Sigurdsson, 1999), subject for art and literature (Sigurdsson and Lopes-Gautier, 2000), and yields resources that society can exploit (Wohletz and Heiken, 1992).
